131255138-Procast-Manual.pdf

ProCAST™ USER’S MANUAL & TECHNICAL REFERENCE

Based on ProCAST™ Version 3.1.0

ProCAST User’s Manual & Technical Reference. Copyright © 1996, 1997 by UES Software, Inc. All rights reserved. Printed in the United States of America. No part of this manual may be used or reproduced in any manner whatsoever without written permission. For information address UES, Software Inc., 4401 Dayton-Xenia Road, Dayton, Ohio 45432-1894, USA. Telephone: 937-426-6900 The following are trademarks or registered trademarks of their respective companies or organizations. PATRAN--PDA Engineering NASTRAN--MacNeal Schwendler Corporation I-DEAS--Structural Dynamics Research Corporation PARASOLIDS--Unigraphics Corporation

UES SOFTWARE, INC. TECHNICAL DOCUMENTATION

USER’S MANUAL & TECHNICAL REFERENCE

TABLE OF CONTENTS INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 1 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 1 General Workflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 6 Graphical Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 8 Manual Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 9 Typographic Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 10 Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 11 Next Step . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 11 STARTING ProCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 13 DATABASE FACILITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 17 TABLE MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 23 VIEWING TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 26 SETTING-UP PROBLEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1 General Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1 Fluid Flow Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 2 Mesh and Material Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 2 Boundary Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 3 Run Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 5 Radiation Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 5 Micromodeling Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 6 Simulating an Al-7% Si Alloy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 8 Inverse Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 11 USING PreCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 1 GEOMETRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 2 CREATE 2-D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 6 Toolbox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 8 ARC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 10 CIRCLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 11 DEL LINE-ARC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 13 DEL REGION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 14 ENCLOSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 15 LINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 16 MESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 17 MOVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 19 QUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 20 REGION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 21 RESTORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 22 REVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 23 SPLIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 24 SMOOTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 25 SYMMETRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 26 GRAVITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 28 CENTRIFUGAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 32 CHECK GEOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 36 AXISYM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 41 VIRTUAL MOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 42 MATERIALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 44 DATABASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 46 THERMAL PROPERTIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 51 FLUID PROPERTIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 55 FILTER PROPERTIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 60 ELECTROMAGNETIC PROPERTIES . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 61 ASSIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 64 STRESS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 68 MATERIAL TYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 70 PROCAST USER’S MANUAL

PAGE

I



PROPERTIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 70 ASSIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 75 MICRO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 77 CAFE MODEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 82 COUPLED EUTECTIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 83 DUCTILE IRON EUTECTIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 87 DUCTILE IRON EUTECTOID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 89 EQUIAXED DENDRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 90 GRAY IRON EUTECTOID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 94 GRAY/WHITE IRON EUTECTIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 95 PERITECTIC TRANSFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 97 SCHEIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 102 SOLID TRANSFORMATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 104 INVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 110 INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 111 DATABASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 113 CREATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 119 ASSIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 121 MULTI-POINTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 124 INVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 128 BOUNDARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 129 DATABASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 131 CURRENT DENSITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 135 DISPLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 136 HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 137 INJECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 140 MAGNETIC POTENTIAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 141 MASS SOURCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 142 MOMENTUM SOURCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 143 POINT LOAD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 144 PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 145 SURFACE LOAD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 146 SURFACE NUCLEATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 147 TEMPERATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 148 TURBULENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 149 VELOCITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 150 VENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 152 VOLUMETRIC HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 153 ASSIGN SURFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 154 ADD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 156 ASSIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 156 COPY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 157 DELETE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 157 DESELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 157 INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 157 LINK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 157 REMAINDER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 158 SELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 158 SELECT ALL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 159 STORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 159 SURFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 159 ASSIGN VOLUME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 161 CURRENT DENSITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 162 MASS SOURCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 162 MOMENTUM SOURCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 162 SURFACE HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 162 VOLUMETRIC HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 162 PERMEABILITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 164 INVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 165 PROCAST USER’S MANUAL

PAGE

II



RADIATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DATABASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EMISSIVITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TEMPERATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VELOCITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENCLOSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ADD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ASSIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DELETE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DESELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SELECT ALL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SOLID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INITIAL CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CONSTANT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EXTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FREE SURFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RUN PARAMETERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UNITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . THERMAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RADIATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FLOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TURBULENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STRESS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ELECTROMAGNETIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 - 166 3 - 167 3 - 171 3 - 172 3 - 173 3 - 174 3 - 175 3 - 175 3 - 176 3 - 176 3 - 176 3 - 176 3 - 177 3 - 178 3 - 180 3 - 182 3 - 183 3 - 185 3 - 186 3 - 188 3 - 189 3 - 195 3 - 199 3 - 202 3 - 210 3 - 212 3 - 214 3 - 216 3 - 218

USING DataCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 1 USING ProCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 1 USING PostCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 1 OPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 3 X-Y PLOT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 4 GEOMETRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 16 RADIATION FACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 17 TEMPERATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 18 PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 22 VELOCITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 23 HEAT FLUX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 24 R, G, L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 25 FEEDING LENGTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 29 ISOCHRONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 31 ALPHA CASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 34 SDAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 36 ROW SUM ERROR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 38 FACE TO GROUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 39 FORMAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 40 STEPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 41 UNITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 43 MATERIALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - 45 USING ViewCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 - 1 CONTOUR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 - 4 VECTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 - 12 STEPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 - 16 PROCAST USER’S MANUAL

PAGE

III



MATERIALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PARAMETERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PAUSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 - 17 7 - 18 7 - 31 7 - 38

USING INVERSE MODELING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 - 1 APPENDIX A INSTALLING ProCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A - 5 APPENDIX B ProCAST FILE USAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PreCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DataCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ProCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PostCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ViewCAST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

B-1 B-1 B-1 B-2 B-3 B-4 B-4

APPENDIX C MATHEMATICAL FORMULATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 1: Energy Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 2: Continuity Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3: Momentum Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 4: Turbulent Kinetic Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 5: Turbulence Dissipation Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 6: Eddy Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 7: Non-Newtonian . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C-1 C-1 C-2 C-2 C-3 C-4 C-4 C-4

Section 8: Initial and Boundary Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C - 7 Section 9: The View Factor Radiation Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . C - 10 Section 10: Finite Element Discretization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Momentum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 11: Time Stepping Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 12: Electromagnetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 13: Stress Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Governing equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermal-Mechanical Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Variational Formulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Finite Element Discretization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C - 12 C - 12 C - 13 C - 15 C - 16 C - 18 C - 20 C - 20 C - 20 C - 21 C - 21

Stress Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C - 22 Radial return mapping algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 14: Preconditioned Conjugate Gradient Solver . . . . . . . . . . . . . . . . . . . . . . . . . . Section 15: Preconditioned Conjugate Residual Solver . . . . . . . . . . . . . . . . . . . . . . . . . . Section 16: Micromodeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Equiaxed Dendrite Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coupled Eutectic Growth Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ductile Iron Eutectic Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gray Iron Eutectoid Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Peritectic Transformation Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solid Transformation Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scheil Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output of Micromodels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PROCAST USER’S MANUAL

C - 25 C - 26 C - 29 C - 30 C - 30 C - 33 C - 36 C - 44 C - 45 C - 47 C - 49 C - 50 PAGE

IV



Equiaxed Dendrite Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coupled Eutectic Growth Model with Instantaneous Nucleation . . . . . . . . Coupled Eutectic Growth Model with Continuous Nucleation . . . . . . . . . . Ductile Iron Eutectic Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gray/White Iron Eutectic Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ductile Iron Eutectoid Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gray Iron Eutectoid Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Peritectic Transformation Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solid Transformation Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scheil Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Interlamellar spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 17: Cooling Curve Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C - 50 C - 50 C - 51 C - 52 C - 52 C - 53 C - 53 C - 54 C - 54 C - 54 C - 55 C - 57

APPENDIX D prefixd.dat FILE FORMAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D - 1 APPENDIX E MATERIAL PROPERTY SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E - 1 APPENDIX F STRESS MODEL PROPERTY SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F - 1 APPENDIX G BOUNDARY CONDITION PROPERTY SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . G - 1 APPENDIX H INTERFACE PROPERTY SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H - 1 APPENDIX I RADIATION PROPERTY SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I - 1 APPENDIX J MATERIAL MICROMODEL PROPERTY SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . J - 1 APPENDIX K INVERSE MODELING FILE FORMATS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K - 1 Inverse settings file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K - 1 Measurement file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K - 3 APPENDIX L INSTALLING INVERSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L - 1 INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

PROCAST USER’S MANUAL

PAGE

V



THIS PAGE INTENTIONALLY LEFT BLANK


PAGE

VI

INTRODUCTION

CHAPTER 1 INTRODUCTION Purpose

ProCAST™ models industrial casting processes and provides tools which may be applied to the analysis of a wide variety of fully coupled thermal, fluid, stress, and microstructure prediction problems. This advanced suite of software modules uses the Finite Element Method and comprehensive solvers to capture all the physics of the casting process and lets you see the effects of design decisions . . . on the computer. Complex geometries including the casting, dies, molds, risers, gates, and chills can be evaluated as a complete system or they may be isolated, depending upon your individual project-specific needs. This User’s Guide and Technical Reference is designed to explain how to use ProCAST, its functions, and options which are available to you.

About ProCAST

ProCAST is and has been the technology leader in the casting simulation market for many years. Key attributes which have contributed to this leadership position are enhanced in the newest release of ProCAST. Some of these attributes are discussed here.

Flexibility: ProCAST can provide both process-specific and analysisspecific simulation support. ProCAST models Sand, Permanent Mold, Low/High Pressure Die, Investment, Expendable Pattern, and Continuous casting processes. ProCAST provides fully coupled thermal-fluid-stress analyses. ProCAST’s micromodeling feature provides the capability to predict the microstructure of castings. Given the required and appropriate material property data, virtually any cast material can be accurately modeled. Graphical User Interface: ProCAST’s graphical user interface has been standardized and structured to guide you through the process for setting-up, running, and analyzing simulation problems. The database facility, table maintenance, and viewing tools are examples of the implementation of this enhanced user interface. The consistent use of visual clues and objects make it easier to concentrate on the casting production problem to be solved. Database Facility: Database capabilities have been integrated into the components of ProCAST. You access the Database Facility through push buttons which appear in selected menus of ProCAST’s functions and components. This facility provides a standardized approach for managing the data associated with your models, whether it is a material, interface definition, boundary condition, or other property or attribute. The nature of the information placed in the database depends upon the material, property, attribute, and/or intended use of the data. Results: Post-simulation processing is robust. ProCAST provides the INTRODUCTION, PAGE 1 - 1

INTRODUCTION

capability to extract and view a comprehensive range of contour and vector plots. For 3D problems, you may view the results from surface and/or internal perspectives at user defined cross-sections. ProCAST’s visualization tools provide the capability to produce animated views of the casting process. These animated displays of material flow and the evolution of strain and temperature in the model, for example, provide further insight into your process, materials, and finished products. You may also export simulation results for analysis with other tools.

Benefits: ProCAST provides the tools to help you build a quality product. The bottom line to any “high-tech” asset is its ability to contribute to your business success. The following are just a few examples of how ProCAST can assist you in achieving these vital business objectives. • Reduce costs • Increase yields • Improve quotes • Improve quality • Boost sales • Shorten cycle times Analytical Application

PAGE 1 - 2


ProCAST is a powerful tool to help you engineer your process . . . to make castings with the required shape and properties, the first time and every time. When you “cast it first on the computer,” you avoid the costly shop floor trial-and-error approach of the past. Some of the analytical capabilities you may apply to your process include: • Heat flow: ProCAST handles all three primary modes of heat transfer--conduction, convection and radiation. It also allows you to account for phase changes (melting, solidification, and solid-state transformation) and internal heat generation or dissipation. • Fluid flow: ProCAST offers outstanding fluid flow capabilities for simulating mold filling. It handles any type of filling, including: plastics, waxes, powdered metals, and the very high velocities encountered in high pressure die casting. Turbulent flow, compressible flow, as well as non-Newtonian flow can be handled. Vents, trapped gas, low pressure casting, lost foam processes, the use of filters, and centrifugal processes can all be accurately simulated. • Stress and Strain: ProCAST calculates thermally induced stresses simultaneously in all components of the simulation with linear elastic, elasto-plastic, or elasto-viscoplastic models. Residual stresses, plastic deformation, hot tears, and final shape of the casting can all be predicted. ProCAST also automatically determines gap formation which results from the heat flow across the interface between the casting and mold in coupled thermal/stress analyses. • Radiation: The advanced radiation module calculates net radiosity using the diffuse grey body approximation technique. View factors, including the shadowing effects, are automatically calculated. The enclosure can move with respect to the casting

INTRODUCTION

and the view factors are automatically updated. ProCAST automatically selects the element faces of the casting which are participating in the radiation model. This capability greatly simplifies problem set-up. • Microstructure modeling: Using deterministic modeling, ProCAST couples the thermal history at any location in a casting with the nucleation and growth of microstructures. The micromodels which have been implemented in ProCAST are designed to be applied to most industrial alloys and are fully coupled with the macro heat transfer solution. • Inverse modeling: Calculates selected material properties by using the numerically generated thermal history and measured temperatures. The inverse solver calculates the optimum material property which will give the best match between the measured and calculated cooling curves for the material. • Electromagnetics: ProCAST is capable of fully coupled thermal/fluid flow/electromagnetic calculations for induction heating and electromagnetic stirring processes. ProCAST solves the Maxwell Equations using a magnetic vector potential approach. • High quality tet mesh: ProCAST automatically generates the mesh for 2D and 3D problems. Geometries which have been produced in a commercially available CAD and CAE packages may be used as input for ProCAST. The MeshCAST module provides the capability to read these geometries, evaluate and repair these geometries, and generate either a 2D or 3D mesh for use in ProCAST. Software features

The suite of tools available to you is governed by your software license. Your professional judgement and individual research, design, development, or analysis requirements govern which of the available tools you will use. The ProCAST suite is composed of six software modules. These six software modules are briefly described below. PreCAST--performs pre-simulation processing by providing the capability to define the problem. This includes importing or creating geometries, defining the materials, interfaces, boundary conditions, initial conditions, planes of symmetry, and run parameters. PreCAST also provides the capability to describe radiation data and apply this data to enclosures and moving solids. DataCAST--reads the problem definition data created by PreCAST, checks the problem definition for errors, converts all units into CGS units and creates the binary files which will be read by the simulation module, ProCAST. If errors are encountered, they will be displayed on the workstation. They will also be written in a file.

INTRODUCTION, PAGE 1 - 3

INTRODUCTION

ProCAST--simulates the casting process, performs the finite element analysis, and generates process results. This data may then be processed for viewing and analysis. PostCAST--provides the post-simulation capability to view X-Y plots, calculate derivative results, and selectively extract data from the simulation results files and format this data for further processing, analysis, or viewing. ViewCAST--provides the capability to view the results of the simulation. It performs rapid contour plots of all results. For example, temperature contours can be plotted at every time step automatically, giving an animated effect. Also, a cutting plane option allows you to see inside the casting. Menus allow you to choose views from an extensive list of contours and vectors. MeshCAST--provides the capability to import geometries from commercially available CAD and CAE packages, evaluate and repair the models, and generate a high quality tetrahedral mesh for use in ProCAST and other FEM analysis software programs. Technical Features

ProCAST offers sophisticated and powerful technology for simulating your casting and casting process problems. Some of the distinctive features of this technology are discussed below. Outstanding fluid flow capabilities for casting simulations are implemented. The full 3D Navier-Stokes equations are being solved with no short cuts, along with the coupled energy equation. A novel implementation of the Volume of Fluid approach has been used for handling the free surface flow during and after filling. Natural convection and shrinkage induced flow are modeled, if desired, throughout the solidification process. A unique method for calculating radiation view factors has been developed for use in ProCAST. It offers radical improvements in computational efficiency over previously existing techniques. It is now feasible to recompute view factors which are changing with time ( as in directionally solidified investment castings ). Complex geometries may be generated using the multi-point constraint feature. This feature allows you “glue” together pieces of a finite element mesh which do not match. Thus, a coarse mesh in one region may be joined to a fine mesh in a second region without a transition. Furthermore, the constraint weighting factors are generated automatically. Accurately model the phase transformation of any alloy or pure metal,

PAGE 1 - 4


INTRODUCTION

to the extent that the fraction solidified function has been quantified, using the enthalpy formulation employed in ProCAST. The latent heat evolution cannot be bypassed with a time step which is too large. Select an implicit mode for the casting and an explicit mode for the die with little restriction on time step size using the two-level time stepping algorithm. The consequence is a substantial savings in CPU time, particularly if there are many elements in the die. The interface heat transfer between the casting and the mold is a dominant rate controlling mechanism. UES engineers have developed a very accurate and efficient coincident node methodology for modeling this phenomenon. Time and/or temperature dependent coefficients can be accommodated. Again, automatic selection of faces makes life easier for the ProCAST user. Specific technical capabilities of ProCAST include the following: • Efficient solution of transient Navier-Stokes and energy equations in three dimensions by the finite element method • Volume of Fluid approach for handling the free surface flow in filling transients • Turbulence modeling using the two equation approach • Trapped gas model accounts for vents and sand permeability • Solves transient, nonlinear heat conduction in three dimensions • Solves the conjugate heat transfer problem with conduction in the solid along with fluid flow • Non-Newtonian flow, with viscosity as a power law function of shear rate • Solidification kinetics and solid state transformations, i.e. micromodeling • Elastic, elastoplastic, and elastoviscoplastic stress analysis, coupled with thermal-fluid analysis • Eddy current heating, Electromagnetics • Enthalpy formulation for handling phase change • Preconditioned conjugate gradient equation solver • Implicit-explicit, two-level time stepping algorithm with automatic step-size control • Temperature dependent density, conductivity, specific heat, viscosity, and emissivity • Coincident and non-coincident node techniques for modeling the casting-mold interface • Time and/or temperature dependent interface heat transfer coefficients • Automatic generation of coincident node faces • Time dependent temperature, pressure, and velocity boundary INTRODUCTION, PAGE 1 - 5

INTRODUCTION

conditions • Time and/or temperature dependent film coefficients for flux boundary conditions • Pressure dependent velocity boundary conditions • Diffuse, gray body radiation model • Automatic view factor calculations with moving relative surfaces • Radial and mirror symmetry options available in the radiation model • Hexahedral (brick), tetrahedron, wedge, quadrilateral, and triangular elements • Multi-point constraints • Automatic calculation of isochrons, temperature gradients, solidification rates, and cooling rates • Automatic calculation of metallurgical indicators for porosity, grain size and morphology, etc. • Temperature-time curve plots • Fraction solid-time curve plots • Sophisticated contour and vector plotting program for viewing all results • Interfaced with PATRAN, IDEAS, IFEM, GFEM, ProEngineer, ANSYS, ARIES and ANVIL for mesh generation The path to follow to take advantage of these and other capabilities in ProCAST, from initial problem definition to analysis of the results, is straight-forward and typically follows the workflow described below. Within the framework of this general workflow, ProCAST offers a variety of tools and methods which may be used to help you refine your model and generate high quality analyses of your casting process. This manual will introduce you to the general ProCAST workflow and provide detailed information about specific commands, functions, keywords, and operations. General Workflow

The work steps which you follow when using ProCAST depend upon the nature of your project, your intended use of the results generated by ProCAST, and the type and quality of model you use as the initial input. The general workflow, outlined below, illustrates the six general steps typically followed in a complete ProCAST project. Step One: Load or create a model Every ProCAST project begins by obtaining a solid mesh of the objects to be analyzed. ProCAST allows you to: 1) read solid meshes which have been created in commercial packages such as PATRAN, IDEAS, ANVIL, ANSYS, ProEngineer, IFEM, and GFEM; 2) sketch 2D geometries and generate a 2D solid mesh with PreCAST’s CREATE 2-D functions; or 3) read an IGES description of a geometry’s surface into MeshCAST and generate a 2-D or 3-D solid mesh.

PAGE 1 - 6


INTRODUCTION

The solid mesh of the model should contain, as a minimum, the following information: • Nodal x, y and z coordinates, • Element connectivity, and • Material number assigned to each element. These options and methods are described in detail in the Using PreCAST section of this manual. Step Two: Set-up the problem PreCAST is used to set-up the problem. Materials, boundary conditions, interfaces, radiation, and initial conditions are defined using PreCAST capabilities. Once these components of the model are defined, they may be assigned to specific mesh elements or groups of mesh elements. Step Three: Check the model DataCAST reads the problem definition data created by PreCAST, checks the problem definition for errors, converts all units into CGS units, and creates the binary files which will be read by the simulation module. If errors are encountered, they should be corrected before proceeding with the simulation step. Step Four: Run the simulation This step actually runs the ProCAST solver. This step involves most of the cpu-intensive computation and is typically run as a batch mode background job. Step Five: Extract the desired results The results of the simulation done in step four will be contained in a variety of files and, in most cases, represents a large volume of data. The unformatted results files are processed in this step by PostCAST or ViewCAST to extract the specific information you need for your analysis. Step Six: View the results ViewCAST is a collection of tools and displays which allow you to visualize the results of the simulation. Steps five and six may be repeated as necessary to provide views of the results which best meet your specific needs. Graphical Interface

ProCAST uses a graphical interface to facilitate input and interaction between you and the components of ProCAST. When the PreCAST, PostCAST, and ViewCAST modules are activated, the work space is filled with a gray background, the UES logo is placed in the lower righthand corner, and a main function banner is displayed. The function banner is a row of push buttons which appear across the top of the work space. The number of buttons shown in a function banner and their INTRODUCTION, PAGE 1 - 7

INTRODUCTION

capabilities depend upon the specific module which has been activated. When a module is active, with very few exceptions, this row of buttons will always be visible. Function banners allow you to move from one capability to another within the specific module. You select from the banner by positioning the cursor over the desired push button and clicking the left mouse button. Each of the push buttons in the function banner result in an immediate action and, depending upon the component of ProCAST, will display either a drop down menu or additional dialog boxes. Each ProCAST component is discussed in this manual. ProCAST allows you to set your own preferences for selected aspects of your workstation environment. These include background and foreground colors and fonts. These preferences are described in Appendix M -- User Preferences. In addition to the graphical interface there are several “hot keys” which have been implemented in ProCAST. These keys or key combinations provide short cuts to commonly performed activities such as zooming and rotating objects displayed in the work window pane.

Hot Keys

The following table summarizes these special keys and the functions they perform. Key, Key Combination, or Mouse button

PAGE 1 - 8


Function Performed

F2

Zoom in by 10%

F3

Zoom out by 10%

X

Rotate about the x axis by 10%

Y

Rotate about the y axis by 10%

Z

Rotate about the z axis by 10%

CTRL+X

Rotate about the x axis by -10%

CTRL+Y

Rotate about the y axis by -10%

CTRL+Z

Rotate about the z axis by -10%

SHIFT+X

Rotate about the x axis by 30%

SHIFT+Y

Rotate about the y axis by 30%

SHIFT+Z

Rotate about the z axis by 30%

CTRL+SHIFT+X


CTRL+SHIFT+Y


CTRL+SHIFT+Z


INTRODUCTION

Key, Key Combination, or Mouse button

SHIFT+LEFT MOUSE BUTTON DRAG MIDDLE MOUSE BUTTON CLICK MIDDLE MOUSE BUTTON CLICK RIGHT

Function Performed

Rotates a rotary toggle switch option list back by one selection Drag cursor with the middle mouse button depressed, zooms on the area in the drag box Repositions the plot: the cursor position becomes the center of the display Zooms out while maintaining current orientation

MOUSE BUTTON

Manual Organization

This manual is organized to provide a reference for each module in the ProCAST suite. Accordingly, there is a section dedicated to the PreCAST, DataCAST, ProCAST, PostCAST, and ViewCAST modules. The MeshCAST module is documented in two separate manuals, MeshCAST Users Manual & Technical Reference and MeshCAST Tutorial & Exercise Manual. These are available under separate cover. Technical reference materials, such as mathematical formulations and file formats have been included in this manual as appendices. In the following pages, each function, keyword and command is discussed in detail. These discussions include descriptions, syntax options, and, in many cases, examples. These discussions have been written in a standard format so that you may quickly find the information you need. The following headings are provided for each topic. In the discussion below, the nature of the information presented in each topic is described. The following outline briefly describes the information presented for each topic. Description: The description states what the function, keyword, command, or interface button does. Method: Method presents a description of how to use the command, feature, or push button. This section discusses all keywords, commands, place holders, optional values, and mandatory alternative choices. When it is appropriate, the syntax for command strings and any required sequence of parameters to enable the function to properly execute is explained. If the function is a graphical interface object, such as a button or menu item, the method section will so state and describe the alternatives and the results to be expected from its activation. INTRODUCTION, PAGE 1 - 9

INTRODUCTION

Remarks: Remarks are used to provide a detailed explanation of the syntax, each parameter in the syntax, the expected results from the function or operation, and the impact of specific keyword or parameter combinations. The level of detail varies depending upon the specific command, function or keyword being described. However, at a minimum, Remarks will explain the intent of each parameter, the options available for each parameter, and any case sensitivities. Remarks are used to provide any special notes, cautions, warnings or tips about the use of the function which may be appropriate. Related Topics: Related Topics is a keyword-oriented cross reference to information which may be of relevance. Related Topics is an optional component of the function write-up. Example: This component may provide one or more illustrations of how this function works. Example is an optional component of the function write-up. Typographic Conventions

PAGE 1 - 10


The following typographic and keying conventions are used in this manual: Bold

Characters or words which appear in a bold typeface are elements which you must use literally. These include: key words, function names, commands,

Italic

Characters or words which appear in an italic typeface represent variable values which you must supply.

[brackets]

Items which are enclosed by brackets [ ] are optional.

{braces|bars}

Characters and/or words which are enclosed by braces { } and separated by a vertical bar indicate a mandatory choice between two or more items. You must choose one of the items unless all of the items are also enclosed in brackets.

ENTER

Words and characters in SMALL CAPITAL letters are used to indicate the name of a keyboard key or key sequence.

ALT+F1

A plus (+) sign between key names indicates a combination of keys which you must depress at the same time. For example, ALT+F1 means to hold down

INTRODUCTION

the ALT KEY while pressing the F1 KEY. Messages

This font (Courier 12cpi) will be used to indicate messages from the software.

Technical Support

Additional technical support is available during normal business hours. You contact the UES Technical Support Staff by: Telephone: 410-573-2037 Facsimile: 410-573-2041 E-mail: [email protected]

Next Step

The recommended next step for using ProCAST and this manual is to read the following topical discussions: Starting ProCAST, Database Facility, Table Maintenance, and Viewing Tools. These topics are included in the introduction and provide information about capabilities and techniques which have been implemented, where applicable, in ProCAST modules.


INTRODUCTION


PAGE 1 - 12


STARTING PROCAST

STARTING ProCAST Description

ProCAST is available in either UNIX workstation or Windows NT versions. The graphical interface and functionality of each of the ProCAST modules is the same in both versions. However, there are slight differences in the method for launching a module based upon the workstation platform. Specific methods for launching the ProCAST System (PCS) or one of its modules will be discussed here. A detailed discussion of any command line parameters for specific modules will be discussed in the respective section of this manual which describes that module.

Method

There are two basic ways to start ProCAST or one of its modules: 1) typing a command line, or 2) clicking on an icon or menu item. The system’s modular structure allows you to launch individual components, such as PreCAST, PostCAST, ViewCAST, etc., by name or select them from a menu on the ProCAST System Interface Screen. This Interface Screen is shown here. It will be displayed if you type “procast” at the NT run or MS-DOS prompt, or type “pcs” at the Unix prompt. You may also initiate this screen by clicking on the ProCAST icon in NT Start Menu.

The options available for initiating any ProCAST session are summarized in a table in the Remarks section of this write-up. When a ProCAST module is started, you must supply a file prefix. ProCAST uses this prefix to uniquely identify the files associated with a specific project or problem.


STARTING PROCAST

There are two ways to enter this file prefix; 1) you may type the desired prefix after the module name in the command line at either a Unix or NT prompt, or 2) you may enter the prefix in a dialog window using the PCS Interface Screen.

At the top of the Interface Screen are two function buttons. The FILE button displays a menu which allows you to specify the prefix and the working directory to be used for this project. This menu is shown here. When you select PREFIX from the menu, a dialog window is displayed.

Type the prefix name in this window and click on APPLY. When you select DIRECTORY from the menu, a dialog window is displayed. Type the directory path and name in this window and click on APPLY. This dialog window is shown here.

Please note: The DIRECTORY dialog window does not create directories; they must be created using the appropriate operating system command prior to running ProCAST.

PAGE 1 - 14


STARTING PROCAST

After you have provided the prefix name and the directory path, you may use the EXECUTE button to display a list of the ProCAST modules. You may select from this list to launch the respective module. The EXECUTE menu is shown here.

The use of the PCS Interface Screen is an optional method for starting ProCAST modules. In both Unix and Windows-NT, you may start the desired module by typing the appropriate information in the prompt window. Additionally, in Windows-NT you may click on Start, select Run, and type the appropriate information in the run dialog window.

Remarks

The following table summarizes the options for initiating a ProCAST module session.

Initiating ProCAST Sessions Windows-NT Method

UNIX

Action

Method

Action

Click on Start, Select Run, Type: procast {prefix} * and click OK

Opens the PCS Screen

N/A

N/A

Click on the ProCAST icon on the NT-Start Menu or Desktop.


Click on the ProCAST icon on the Desktop. **



At the Unix prompt type: pcs {prefix} * and press ENTER.


Starts the respective module.

At the Unix prompt type: the module name {prefix} * and press

Starts the respective module.

at the MS-DOS prompt and press ENTER. At the MS-DOS prompt type: the module name {prefix} and press ENTER.

***

ENTER.

*** INTRODUCTION, PAGE 1 - 15

STARTING PROCAST

Initiating ProCAST Sessions Windows-NT

UNIX

*Entering the prefix in these commands will place the entered value in the prefix dialog box. **Assuming that your Unix release supports this option.

***Options and/or parameters for each module are discussed in each module’s section of this manual. If you type a ProCAST module name (except MeshCAST) at either the MS-DOS prompt, the NT-Run dialog window, or the Unix prompt and do not provide a prefix name, you will receive a prompt message to enter a prefix. If you are using the NT version, and would like to specify a directory on another disk, type the following in the directory dialog window: //x/path/prefix where: x = the drive name path = the path name prefix = this project’s name Some modules have unique command line options. These are described, as necessary, in the respective chapter in this manual. Related Topics

PAGE 1 - 16


Using PreCAST, Using DataCAST, Using ProCAST, Using PostCAST, Using ViewCAST

DATABASE FACILITY

DATABASE FACILITY Description

The Database Facility has been integrated into PreCAST. Access to the Database Facility is based upon push buttons which appear in selected menus of PreCAST functions and components. For example, when you select MATERIALS, INTERFACES, BOUNDARY CONDITIONS, or RADIATION from the Main Function Banner, a drop down menu will be displayed. One entry in these menus is DATABASE. Selecting the DATABASE entry from these menus will open additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. ProCAST’s Database Facility provides a standardized approach for managing data. Its graphical interface provides guidance in entering, maintaining and managing the data associated with your models. The nature of the information to be placed in the database depends upon the property, material, attribute, or intended use of the specific data. The Database Facility is discussed in this section. Specific options for each use of the DATABASE will be discussed in more detail in their respective sections of this manual.

Method

The figure shown here illustrates the menu which is displayed when the MATERIALS function in the Main Function Banner is activated. To use the Database Facility click the click on the DATABASE push button. The Database Facility is context sensitive and will display data elements from the database based upon what you are doing and where you are in PreCAST. Clicking the DATABASE push button will result in the immediate action to display a table containing any appropriate data elements which may be in the database. For illustration purposes we will use the DATABASE function in the MATERIALS menu. The figure shown here is a table which contains a list of the materials in the database.


DATABASE FACILITY

Along the top of the table is a group of push buttons which provide access to specific database functions. The heading for the table, which appears below these push buttons and above the table entries, will change depending upon the database elements being displayed. When you select a function from this group of push buttons, additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus will be displayed. These graphical interface tools will guide you through the process working with information in the database. The syntax for each of these data elements and any specific input rules will be explained in the appropriate section of this manual. The scroll bar at the left side of the table allows you to move through table entries, if the number of table entries in the database exceeds what can be displayed at one time. Remarks

ProCAST provides the capability and flexibility to read, add, copy, modify, or delete data in its databases. You cannot delete or modify the base set of material data elements which come with ProCAST. However, you can copy an entry, rename it, and modify the newly created entry. You may only delete those data elements which you have added to the database. The major capabilities of the Database Facility are described here. Specific examples of each type of data element and their respectively

PAGE 1 - 18


DATABASE FACILITY

required options are provided in the appropriate sections of this manual. READ Provides the capability to read and/or modify detailed information about a specific table entry in the database. You select the desired table entry by clicking on it. The background of the selected table entry will turn red. Once a table entry has been selected, click on the READ push button. This will result in the immediate action to retrieve the data associated with this table entry and display it in an appropriate format. From this display you may be able to select additional levels of detail for viewing. The figure shown here illustrates the data which is displayed because we selected the IRON_Pure entry in the MATERIALS DATABASE.

As seen in this example, you may view additional details associated with IRON_Pure, by clicking any of the check boxes. Each of these check boxes, in this example, correspond to material properties. The check boxes are shaded according to the following criteria: if the box is blue, e.g., Conductivity, Density, etc., it indicates that some data has been put in the database for this property. If the box is red it is currently selected, and if the box is gray, no data has been put in the INTRODUCTION, PAGE 1 - 19

DATABASE FACILITY

database for this property. If this database entry has your USER name, you may change data or add data elements to this entry. You may store any data you may have entered by clicking the STORE push button at the bottom of the display. This will store the data in the database and close the display. You may close the display without storing any data you may have entered by clicking the CANCEL push button at the bottom of the display. ADD Provides the capability to add a data element to the database. You activate the ADD function by clicking the ADD push button. This results in the immediate action to display a blank Input Data Box. In this example adding a material would display an input box like the one shown here.

It is important to note that, in some cases, some input options may not be appropriate or may be mutually exclusive. In those cases, unavailable option check boxes will be red. PAGE 1 - 20


DATABASE FACILITY

You may store any data you may have entered in the Input Data Box by clicking the STORE push button at the bottom of the box. This will store the data in the database and close the Input Data Box. You may close the Input Data Box without storing any data you may have entered by clicking the CANCEL push button at the bottom of the box. COPY Provides the capability to copy the data associated with one table entry and rename it. You select the desired table entry by clicking on it. The background of the selected table entry will turn red. Once a table entry has been selected, click on the COPY push button. This will result in the immediate action of displaying a Text Input Box , as shown here. Type the name of the new entry in the Text Input Box and press the ENTER key. This will create the new database entry. DELETE Provides the capability to delete the data associated with one table entry. You may only delete an entry from the database if you are the one who created it, i.e., it has your USER name. You select the desired table entry by clicking on it. The background of the selected table entry will turn red. Once a table entry has been selected, click on the DELETE push button. This will result in the immediate action to display a Confirmation Window as shown here. To confirm the deletion, click on the CONFIRM push button. This will delete the database entry. This is not reversible after the confirmation. To cancel the deletion, click on the CANCEL push button. This will cancel the deletion and close the confirmation window. Related Topics

TABLE MAINTENANCE, MATERIALS, INTERFACES, BOUNDARY CONDITIONS, RADIATION, MICRO, STRESS


TABLE MAINTENANCE

TABLE MAINTENANCE Description

Table Maintenance describes ProCAST’s standardized approach for entering data in tables. These table maintenance techniques are used most heavily in PreCAST. As discussed in the DATABASE FACILITY section of this manual, database entries are displayed in a tabular form. You may also use these tabular forms for supplying data for inclusion in a database. Additionally, ProCAST frequently uses a tabular format for creating lists other than database entries. Specifying Step Values and Specifying Temperatures in PostCAST’s OPTIONS menu are two examples where this Table Maintenance approach is used. Where Table Maintenance is used, the number of columns in a given table display will vary depending upon the type of data and its intended use. Specific options for each type of data element will be discussed in more detail in their respective sections of this manual. The figure shown here illustrates a tabular display of the Conductivity property for a material. The main parts of the table display are: the Table Function Table Function Push Buttons Push Buttons, Table Heading(s), Rotary Toggle Switches, Table Table Heading(s) Entries, and the Edit Value Input Box.

Method

Rotary Toggle Switches

The number of columns displayed and the presence of rotary toggle switches and their respective optional values will depend upon the exact nature of the data to be entered and the valid attributes for each specific data element as defined by ProCAST.

PAGE 1 - 22


Table Entries

TABLE MAINTENANCE

The Table Function Push Buttons may be activated by clicking on the desired function. These functions accomplish the following activities. SAVE This Table Function stores the contents of the table in the appropriate database. If you have added or changed any table entries, these will be saved at this time. GRAPH This Table Function will graph the data points which are contained in the table entries. There must be at least two rows filled out for the function to be graphed. An information message will be displayed if there are an insufficient number of data points to plot the graph. If there are no table entries, the GRAPH push button is ignored. The figure shown here illustrates the graph of the data in the associated table.

ERASE This Table Function will delete the entire contents of the table. This operation is not reversible. QUIT This Table Function will result in the immediate action to close the table display. The data is not stored automatically. Therefore, any data or changes which you have not stored, will be discarded. Rotary Toggle Switches allow you to select a value from the list of valid entries defined by ProCAST. You select the desired value by clicking the toggle switch in the table display. This button is a rotary push button. Each consecutive time you click on the button, the next option in the list is displayed as the label of the button. The valid choices and the default value, if any, will be described in the appropriate sections of this manual. If you change a toggle switch setting, you must use the INTRODUCTION, PAGE 1 - 23

TABLE MAINTENANCE

STORE Table Function to retain the change in the database. Entering data in the table is done by first selecting the desired table entry. You select a table entry by clicking on it. If the table is empty, select the area in the first row under the first column heading. This is illustrated in the figure shown here. If the table has data and you want to add another data element, use the scroll bar, if necessary, to move to the end of the table and select the first empty area under the first column. Once a table entry is selected the background of that entry will change to red and the cursor will be placed in the Edit Value Input Box. If the entry contains data, the data will be displayed in the Edit Value Input Box. You may then enter or change the data in the Edit Value Input Box. When you are satisfied with the new data, press ENTER. This will place the value in the highlighted table entry and move the cursor to the next available table entry. Remarks

It is important to note that data elements which are entered or changed in the Table Display are not saved in the database until you use the STORE Table Function.

Related Topics

DATABASE FACILITY, MATERIALS, INTERFACES, BOUNDARY CONDITIONS, RADIATION, MICRO, STRESS

PAGE 1 - 24


VIEWING TOOLS

VIEWING TOOLS Description

VIEWING TOOLS have been integrated into ProCAST components as a standard set of tools which are available and visible any time there is a geometry displayed in the work window pane. These tools provide the capability to manipulate the geometry in this window. You may use these tools to facilitate viewing and working with all or part of the geometry.

Method

The figure shown here illustrates the tools available in the VIEWING TOOLS toolbox. To use a viewing tool, click on it when the cursor is over the desired function. When you select a tool, ProCAST will perform the designated function or open an additional input display. You may use these input displays to provide additional instructions or other directions as to how the selected tool is to be used. For example, when you select the ROTATE function, an input display will be opened to allow you to input the amount and direction of the rotation. The method, syntax, and use of the Viewing Tools will be discussed in this section of the manual. For convenience of presentation, they will be presented in alphabetical order. CENTER--Use this push button to reposition a point in the geometry to the center of the work area. The point you pick will be moved to the center of the work window pane. Turn this function on by clicking the left mouse on the CENTER button in the tool box. The button will turn red when it is active. The figure shown here illustrates this activity. In the figure on the left, the cursor is selecting the point to be “centered”.

After Center

Before Center

The figure on the right shows the geometry as redrawn with the INTRODUCTION, PAGE 1 - 25

VIEWING TOOLS

point we selected in the center of the work window pane. To reposition the geometry, move the cursor to the point in the window you want moved to the center of the work area and click the left mouse button. Once the geometry has been redrawn, the background of the push button will return to gray. CENTER allows you to reposition the geometry into the center of the work area. You may choose any part of the window to be centered. CENTER determines the point about which rotations take place. It will redraw the geometry or the portion of the geometry being displayed at the time you click the left mouse button. DRAG--Use this push button to reposition the geometry to a specific point in the work area. Turn this function on by clicking the left mouse on the DRAG button in the tool box. The button will turn red when it is active. The figure shown here illustrates this activity. In figure on the left, the cursor is selecting the point to which we will “drag” the center of the geometry.

Before Drag

After Drag

The figure on the right shows the geometry as redrawn with the center of the geometry at the point we selected. DRAG allows you to reposition the geometry by shifting the geometry to the point you select with the cursor’s position. The green cross will remain in the same position on the model, but you can move the cross and the model along with it to a new location. Once the geometry has been redrawn, the background of the push button will return to gray. DRAG does not have any effect on the geometry. It will redraw the geometry or the portion of the geometry being displayed at the time you click the left mouse button.

PAGE 1 - 26


VIEWING TOOLS

ELEMENTS---Use this push button to display the Element ID Numbers for each element of the mesh which is in the work window pane. You select this function by clicking the ELEMENTS push button. The element IDs will be drawn in green for each element currently being displayed. This is illustrated in the

figure shown here. This display capability does not alter the model or the mesh. It allows you to focus on specific portions of the model for analysis. Using the ELEMENTS tool just after using the HIDDEN tool will limit the elements labeled to the visible surface elements. ENCLOSURE--Use this toggle switch to turn on any enclosure elements for viewing along with the casting. Normally, you would only have enclosure elements for a view factor radiation model. Turn this function on by clicking the left mouse on the ENCLOSURE button in the tool box. The button will turn red when it is active. Successive clicks on the ENCLOSURE button will toggle the viewing of enclosure elements between the ON and OFF. HIDDEN--Use this push button to display a hidden surface view of the mesh so that only the visible surfaces of the mesh will show. This is particularly useful for verifying the orientation of the model. Turn this function on by clicking the left mouse on the HIDDEN button in the tool box.


VIEWING TOOLS

MAT SELECT--Use this push button to selectively display portions of

the mesh based upon their material ID. When you select this function by clicking the left mouse button on the MAT SELECT push button, ProCAST displays a tabular list which contains the material IDs and the material names in the model. This list is illustrated in the figure shown here. All of the active materials will be highlighted with a red background in the list. In this illustration, the model contains three Material IDs. Only two of these materials have been selected as active. You may activate or deactivate a material by clicking on the desired row in the list. Successive clicks will toggle between the activated and deactivated. When you are satisfied with the materials you have selected, click on the QUIT push button. The Material List display will close and the work area will be redrawn showing only those materials you set to be active. This display capability does not alter the model or the mesh. These capabilities allow you to focus on specific portions of the model for analysis.

PAGE 1 - 28


VIEWING TOOLS

NODES--Use this push button to display the Node ID Numbers for each node of the mesh which is in the work window pane. You select this function by clicking the NODES push button. The node numbers will be drawn in red for each node currently being displayed. This is illustrated in the figure shown here. This display capability does not alter the model or the mesh. It allows you to focus on specific portions of the model for analysis. Using the NODES tool just after using the HIDDEN tool will limit the nodes labeled to the visible surface nodes. RESTORE--Use this push button to restore the geometry to its original view in the work window pane. Any rotation, node or element display, zoom or repositioning you may have done while working with this geometry will be reset. Activate this push button by clicking the RESTORE button in the tool box. ROTATE--Use this push button to rotate the image in the work window pane. When you click on the ROTATE push button an input display will be shown. This is illustrated in the figure shown here. Select the degree of rotation about each or every axis by moving the slider in one or more of the horizontal scroll bars. You may move the slider by clicking the left mouse button on either of the directional arrows, by clicking the left mouse INTRODUCTION, PAGE 1 - 29

VIEWING TOOLS

button in the slide track, or by clicking and dragging the slider. You may specify the direction of rotation by clicking the “+” and “-” toggle buttons. These buttons are located to the right of each scroll bar. The maximum amount of rotation, per axis, which may be specified at one time is 180 degrees. The degree of rotation may be set in each of three scroll bars and in a positive or negative direction. However, the image will not be rotated until you click on the ROTATE push button. Selecting the degree of rotation by clicking the directional arrow at either end of the scroll bars will move the slider one degree at a time. Selecting the degree of rotation by clicking in the slide track will jump the slider. Dragging the slider selects the degree of rotation in a continuous manner proportionate with the extent of the mouse movement and the speed at which the mouse moves. Note that the rotation is about the global triad which appears in the lower left corner of the display screen. The “right-hand” rule is used. Click on the ROTATE push button in the control box to have the image moved after you have set the desired degrees of rotation. or Click on RESET to reset all scroll bars to zero and the toggle buttons to “+” without moving the image. or Click on the QUIT push button in the control box to close the control box without resetting any values you may have specified or moving the image. ZOOM--Use this tool to enlarge or shrink the image in the work window pane. When you click on the ZOOM push button an input display will be shown. This is illustrated in the figure shown here. Select the amount of enlargement or shrinkage by moving the slider in the horizontal scroll bar. You may move the slider by clicking the left mouse button on either of the directional arrows, by clicking the left mouse button in the slide track, or by clicking and dragging the slider. Moving the slider toward the “-” shrinks the image; toward the PAGE 1 - 30


VIEWING TOOLS

“+” enlarges the image. The maximum range of magnification or zoom factor is from .01 of the image to 10 times the size of the original image. The degree of magnification or shrinkage may be set in the scroll bar. However, the image will not be adjusted until you click on the ZOOM push button. Selecting the degree of magnification by clicking the directional arrow at either end of the scroll bar will move the slider in small increments. Selecting the degree of magnification by clicking in the slide track will jump the slider in larger increments. Dragging the slider selects the degree of magnification in a continuous manner. Click on the ZOOM push button in the control box to have the image moved after you have set the desired degree of magnification. or Click on RESET to reset the scroll bar to zero without moving the image. or Click on the QUIT push button in the control box to close the control box without resetting any value you may have specified. Related Topics

HOT KEYS


SETTING-UP PROBLEMS

CHAPTER 2 SETTING-UP PROBLEMS General Principles

When setting up any type of ProCAST analysis, you should keep in mind the following guidelines: 1. Node and element numbers must be sequential starting from 1. 2. All nodes must be referenced by a least one element. 3. All solid elements must have a material ID. Enclosure elements do not need a material ID. 4. In general, the denser the mesh, the greater the accuracy of the results and the longer the cpu time. By judicious selection of mesh densities, you can often obtain acceptable accuracy with substantially less simulation time. Concentrate your elements in areas of high gradients (temperature or pressure), such as at the casting walls. 5. It is usually better in terms of accuracy to build the mesh for the mold as well as the casting. It is sometimes possible to mimic the effect of a mold by applying heat flux boundary conditions directly on the casting surface. This can save cpu time because of the reduced number of elements. However, it is often difficult to predict how the mold will behave, especially if cooling lines are involved, and therefore determining the appropriate boundary conditions is not straightforward. 6. Coincident node interfaces can be automatically constructed by PreCAST where elements with dissimilar material IDs meet. Each coincident interface is uniquely identified by the material ID numbers on either side of the interface. If two materials in your model meet in several different regions which require varying coincident heat transfer characteristics, you must insure that unique material ID sets will exist at each interface. 7. Multi-point constraints are also automatically generated by PreCAST when nodes of one region lie on the faces of elements in another region. As in the case of the coincident nodes, the two regions involved are defined by having different material ID numbers. Therefore, if two pieces of iron ( having identical material properties ) meet in such a way as to require a multi-point constraint interface, each piece would be given a unique material ID number. In PreCAST, both pieces can be assigned the identical material properties. 8. Multi-point constraints can not be generated across a coincident node interface. 9. The effect of a complete die cycle can be captured by placing a heat boundary condition on the coincident node interface between the casting and the mold. Time functions which toggle between values of 1 and 0 or vice versa can alternately turn on the interface heat transfer or the boundary heat transfer. 10. You can use the EXTRACT option in PreCAST to take the SETTING-UP PROBLEMS, PAGE 2 - 1

SETTING-UP PROBLEMS

temperatures of the mold from the end of one cycle and use them for the initial temperatures of the next cycle. 11. After running DataCAST, you should always examine the prefixd.out file. Error or warning messages will be written at the top of this file. DataCAST will convert any quantity units into CGS units and the results will also be written in this file. If something looks out of the ordinary may indicate an error in data input. The volumes of each material ID are written, in cm3, in the material data summary . 12. Run the problem in ProCAST for 10 time steps. Use the post-processing features of ViewCAST to see if, the temperature initial conditions are correct, the temperature drops across the coincident interfaces are reasonable, temperature fields have continuity across the regions where multi-point constraints exist, heat fluxes have the right magnitude, and symmetry faces are experiencing zero flux. Fluid Flow Analysis

Setting up a casting problem for a "fluid and thermal" analysis does not require much additional effort as compared to a "thermal only" analysis. The analyst needs only to provide a few additional pieces of information. Mesh and Material Properties 1. Since no-slip velocity conditions are normally placed everywhere the metal comes into contact with the mold, each fluid channel should be at least two elements wide. This would provide only one "free" node within the channel, providing only a very coarse estimate of the fluid profile. A channel with at least four elements across would be more desirable. 2. Wedges, tetrahedrons, and triangles should be used with care in fluid analyses. All these element types have the potential to be placed in such a way that all of their nodes lie on the boundary. When this happens, all the nodal velocities are fixed and the pressure in the element becomes indeterminate. These are known as "dead" elements. Many times these elements have a minimal effect on the analysis. You can usually avoid this situation by splitting up the meshing volumes such that all the elements have at least one node which is not on the boundary. Using brick or quadrilateral elements will usually eliminate this concern. 3. Any material which will be flowing needs to have the properties of viscosity, liquidus and solidus temperatures specified, in addition to the usual thermal properties. Not all the materials in the ProCAST database have this data, so be careful. Viscosity, in particular, is often times hard to come by for alloys. Using the viscosity for the corresponding pure base metal is a good first approximation.

PAGE 2 - 2


SETTING-UP PROBLEMS

Boundary Conditions In general, every boundary of the fluid domain requires either a velocity or pressure boundary condition, sometimes both. In most situations, this means that you have to specify the conditions at the inlets and outlets. The following types of fluid boundary conditions are used in ProCAST: 1. No-slip conditions specify a zero velocity on a stationary surface. PreCAST will automatically put a no-slip boundary condition at all the coincident interface nodes. If the mold walls are not included in the model, no-slip boundary conditions should be imposed by specifying a zero u, v, (and w in 3--D) velocities. No time and/or pressure functions are appropriate for this type of boundary condition. 2. Specified Velocity conditions are used to set non-zero velocity vectors on inflow and outflow. For 2D analyses, both the u and v velocity components must be specified, even if one of them is zero. Likewise, for a 3D analysis, all three velocities must be specified. These boundary conditions can be given as constants or can be functions of time and/or pressure. 3. Specified pressure conditions can be used as inflow or outflow conditions or on free surfaces. In some cases it may be used to simply set a reference pressure. Pressure boundary conditions can be constant or time varying. ProCAST will automatically set the pressure to zero on the free surfaces in the model. If the gas model is utilized, then the pressure on each free surface will be controlled by the gas model. All models, whether they are free surface or not, should have at least one specified pressure somewhere in the fluid region. If no specified pressures are given in a free surface model, the calculation will be fine until the free surface is forced out of the model. Once filled, a specified pressure condition is needed. 4. Symmetry conditions force the velocities to align with the symmetry planes such that the normal components are zero. 5. Periodic conditions link two periodic surfaces together. Pressures along the periodic surfaces are equated. The velocities are linked via the appropriate transformation. It is important to note that the "natural" boundary condition for the pressure equation is a zero gradient normal to the wall. This situation promotes a velocity field which runs parallel to the wall, which is usually desirable. Therefore, in situations when the flow does not run parallel to a wall, either a velocity or a pressure boundary condition is required. Example 1

SETTING-UP PROBLEMS, PAGE 2 - 3

SETTING-UP PROBLEMS

First, consider an axisymmetric geometry as shown below. The filling transient is not considered in this analysis. Instead, the subsequent circulation flows are of interest. This analysis can be run one of two ways: 1) the free surface model can be used which will include the effects of the liquid level dropping in the risers, or 2) these effects can be ignored and the free surface model will not be actuated.

metal

C

L

mold

The following fluid boundary conditions are required whether or not the free surface model is used: 1. u = 0 along the center line (a symmetry condition could be used just as well). 2. P = 0 along the tops of the risers (if the free surface touches the top row of nodes, this boundary condition will be needed). 3. u = v = 0 along the coincident interface. This boundary condition will automatically be included by PreCAST. The free surface model will work best if there is at least one empty row of elements at the top of the risers. The initial free surface level can be adjusted using the LVSURF parameter in the prefixp.dat file or in the RUN PARAMETERS function of PreCAST. Example 2 A simple filling analysis is considered next. In this analysis, the mold is not included. Top of riser

The boundary conditions for this model are as follows: 1. u = u_inlet, v = 0 at the filling gate 2. P = 0 along the top of the riser 3. u = v = 0, everywhere else It is important to specify no-slip velocities last when working in PreCAST. Specified velocities are imposed in sequential order. In that way, no-slip velocities will overwrite inlet velocities at the edges of the inlet region, as they should.

mold

Filling gate

gas

metal

Example 3 In the next model, a pressurized gas PAGE 2 - 4


SETTING-UP PROBLEMS

region is used to drive the metal into the upper mold region. The analysis is started with the lower melt area already filled. The boundary conditions for this analysis are: 1. Symmetry condition specified along the left edge of the model. 2. The pressure boundary condition will be governed by the gas model. If an injection is specified into the gas region above the melt, then the pressure will be mechanistically computed for that expanding region. The pressure on the metal surface being forced up the sprue will be determined by considering vents and/or gas porosity within the mold. 3. No-slip boundary conditions will be imposed for the interface by PreCAST. More no-slip boundary conditions are required down in the melt area. Run Parameters Some of the parameters in the prefixp.dat file need special attention for a flow analysis. 1. FLOW = 1, turns the flow model on 2. COURANT = 10. to 50. Higher courant limits will allow the use of larger time steps. However, if excessive restarts are the result, the courant number should be reduced. 3. LVSURF = 0.98 will switch from the filling model to a circulatory flow model when the metal region is 98% full. If the switch is undesirable, then set LVSURF > 1.0. 4. CONVV = 0.05, sets the velocity convergence to 5 percent. This will require the velocity predictions of the momentum equations to stabilize to within 5 percent at each time step. Adjusting this parameter up or down may have a large effect on the allowable time step. Radiation Problems

The effects of radiation can be handled either by the "simple" method, where you specify an emissivity and an ambient temperature in a heat flux boundary condition, or the more sophisticated view factor method. The comments below are directed towards this latter class of problems. 1. A heat flux boundary condition, containing an emissivity and with view factors turned on, should be applied to all external surfaces of the casting, with the exception of symmetry faces. 2. The view factor radiation model requires a totally enclosed system. Any gaps in the enclosure behave like "black holes" through which energy escapes, yielding unpredictable results. When analyzing a casting with planar or axial symmetry, make sure that the correct angles are being subtended, such that if the symmetric portion of the enclosure was rotated around, the casting would be totally surrounded. Also, if the enclosure is moving relative to the casting or vice versa, make sure that the casting will not penetrate through the walls during the course of the analysis. SETTING-UP PROBLEMS, PAGE 2 - 5

SETTING-UP PROBLEMS

3. The walls which comprise the enclosure in a 3D radiation analysis may be modeled with 2D elements, i.e., triangles and quadrilaterals, or by solid elements. Similarly, in a 2D radiation analysis, the enclosure may be built with either 1D bar elements or 2D solid elements. 4. If 2D elements are used to build the enclosure in a 3D problem, make sure that the normal vectors of these elements are facing inward. Also, at a minimum, you need to assign temperatures and emissivities to these types of elements (and to 1D elements in a 2D problem). 5. If 3D elements are used to build the enclosure, a heat flux boundary condition, containing an emissivity and with view factors turned on, should be applied to all the inwardly directed faces. Take care not to apply this type of boundary condition, with view factors on, to the outside of a solid element enclosure. 6. Place your global coordinate system near the geometric center of your casting. This will ensure maximum numerical accuracy in the view factor calculations. 7. Setting RDEBUG to 6 under the RUN PARAMETERS will cause ProCAST to produce the prefix.view and prefix.serr files after the first time step. These can be quite useful in debugging problems with the geometry or radiation boundary conditions. These files contain, respectively, face to group view factors and row sum errors. Contour plots of these quantities can be produced by ViewCAST. 8. If you are modeling one component of a symmetric structure, you can use ViewCAST to replicate the symmetric parts. Then you can verify that there are no overlapping regions or gaps present in your model. 9. Use PostCAST to output a radiation face neutral file, prefixr.ntl. Use PATRAN or IDEAS to look at this model to verify that there are no holes in the radiation model. 10. After enough time steps have been computed, check that the enclosure is moving at the right speed. You can see this with ViewCAST. Micromodeling Analysis

PAGE 2 - 6


The ultimate aim of micromodeling is to predict the microstructure of castings. The mechanical properties of the castings can then be predicted from a knowledge of the microstructure. Micromodels can not accomplish this task alone however. They have to be incorporated into macromodels to achieve this goal. The coupling of the macro- and micromodels can be accomplished through the source term in the energy equation. The rate of evolution of the fraction of solid is calculated by the micromodels, which controls the release of latent heat.

SETTING-UP PROBLEMS

Liquid

Liquid + Delta

Delta

Peritectic Reaction

P

Delta + Gamma

Liquid + Gamma

Liquid + Graphite

G Gamma A

E

Eutectic Reaction Gamma + Graphite Gamma + Ferrite

Eutectoid Reaction D Ferrite + Graphite

Ferrite Fe

X wt % C

Figure 2-1 Binary Stable Fe - C Phase Diagram

Figure 2-1 illustrates a stable binary Fe-C phase diagram, showing three types of major reactions: 1. Peritectic Reaction (P) : L + 2. Eutectic Reaction (E) : L + Gr 3. Eutectoid Reaction (D) : + Gr Where L symbolizes liquid, and stand for two different types of body centered cubic (b.c.c.) ferrite, stands for the face centered cubic (f.c.c.) austenite phase, and Gr stands for graphite. Take, for example, a gray iron alloy of carbon equivalent X. Solidification will begin at point G on the phase diagram by forming austenite dendrites. Austenite dendrites will continue to form until the eutectic temperature, given by the line AE, is reached. At this time, all the remaining liquid undergoes a transformation by which the liquid solidifies as austenite and graphite. As the temperature continues to drop, the solute concentration ( i.e., the carbon concentration ) decreases following the AD line. When the eutectoid temperature corresponding to the point D is reached, the austenite phase transforms into ferrite and graphite. Micromodels are activated in ProCAST by choosing a suitable value for the MICRO parameter in the prefixp.dat file. The following table lists values for the MICRO parameter corresponding to the different micromodels:


SETTING-UP PROBLEMS

MODEL

MICRO

Eutectic Ductile Iron

1

Equiaxed Dendrite

2

Coupled Eutectic with Instantaneous Nucleation

4

Coupled Eutectic with Continuous Nucleation

8

Eutectic Gray/White Iron

16

Eutectoid Ductile Iron

32

Gray Iron Eutectoid

64

Peritectic Transformation

128

Solid State Transformations

256

Scheil Model

512

A combination of different micromodels can be chosen in a single run by adding the appropriate MICRO parameters corresponding to individual micromodels. When you run a PreCAST session and assign the desired micromodels to the particular material, the MICRO parameter is automatically assigned the right value. In our example, the equiaxed dendrite solidification beginning at point G is activated by setting MICRO to 2. The eutectic transformation at AE is turned on by adding 4 to MICRO, which activates the Coupled Eutectic Model with Instantaneous Nucleation. The MICRO parameter will be automatically be assigned a value of 6. The MFREQ parameter in the prefixp.dat file governs the frequency at which the relevant microstructural results are stored for restart purposes and for post-processing. Giving the LINSRC parameter a value of 1 in the prefixp.dat file switches on linearization of the source term. In this option, a part of the source term is added to the system matrix, thereby enhancing stability. Simulating an Al-7% Si Alloy

PAGE 2 - 8


There is more to running micromodeling analyses than setting the parameters described above. Some material data about the alloy also has to be supplied. Suppose that you want to simulate the solidification of an Al-7%Si alloy in a sand mold. Consider the binary phase diagram, shown in Figure 2-2, for the Al-Si system. For this alloy, equiaxed solidification begins when the liquidus temperature, 618(C, is reached. Equiaxed dendrites continue to grow until the eutectic temperature, 577(C, is reached and eutectic solidification begins.

SETTING-UP PROBLEMS

1414 L

660.5 618 577 Al Si

Al

1.6

7

12.6

wt % Si

Si

Figure 2-2 Binary Al - Si Phase Diagram

Note the following aspects of the above phase diagram: 1. Melting point of pure Al = 660.5(C 2. Melting point of pure Si = 1414(C 3. Alloy composition = 7% 4. Eutectic temperature = 577(C 5. Primary transformation temperature = 618(C 6. Liquidus slope, taken as constant = (577--660.5)/12.6 = 6.63(C/wt% 7. Solute partition coefficient, taken as constant = 1.6 / 12.6 = 0.13 (evaluated at eutectic temperature). We will model this alloy with a combination of equiaxed dendrite and coupled eutectic solidification with instantaneous nucleation. 1. In the MATERIALS menu, select MICRO and then press the ADD button. Select EQUIAXED DENDRITE.. 2. Give the GIBBS---THOMPSON COEFF a value of 2.0e-7 mK. ( Kurz and Fisher, Fundamentals of Solidification ) 3. ALLOY COMPOSITION = 7.0 4. TRANSF. TEMP = 618(C (assuming that it does not vary with cooling rate) 5. PARTITION COEFF. = 0.13 6. DIFFUSIVITY = 3.0e-9 m 2/s 7. LIQUIDUS SLOPE = -6.63(C/wt% 8. SUBSTRATE DENSITY: Suppose you obtained from experiment that the grain size in the castings varies from 0.032 cm to 0.052 cm when the corresponding cooling rates vary from 0.2 (C/s to 10 (C/s. Using the equation,


SETTING-UP PROBLEMS

4 3

%

RL # N 1 3

(3.4.1)

where RL is the grain size and N is the substrate density, the following table may be constructed: Cooling Rate ((C/s)

Substrate Density (cm-3)

0.2

1697.86

10

7285.53

9. Click on STORE. 10. In the MATERIALS menu, again select MICRO, then ADD. Select COUPLED EUTECTIC, then INSTANTANEOUS NUCLEATION. We make an assumption of stable eutectic growth. 11. STABLE GROWTH CONSTANT = 1.0e-5 cm/sec/K2 12. METASTABLE GROWTH CONSTANT = 4.0e-5 cm/sec/K2 13. SOLVENT MELTING POINT = 660.5 (C 14. CRITICAL COOLING RATE = 300 (C/s 15. EUTECTIC COMPOSITION = 12.6 16. TRANSF. TEMP = 577 (C 17. PARTITION COEFF. = 0.13 18. Let us assume that you obtained the following data from experiment: Cooling Rate ((C/s)

Substrate Density (cm-3)

0.5

1.0e5

12.2

4.0e5

Here substrate density refers to eutectic cell density, which can be measured by simple metallographic analysis of the microstructure.

PAGE 2 - 10


SETTING-UP PROBLEMS

19. The LAMELLAR SPACING table is arbitrary in this case because we already chose to avoid a metastable eutectic structure by intentionally inputting a high value of the CRITICAL COOLING RATE, i.e., 300 (C/s. However, for the sake of completion, you may enter following data: Note that with an increase in the cooling rate, the lamellar spacing decreases. Cooling Rate ((C/s)

Lamellar Spacing ()m)

0.3

10

15

2

20. Click on STORE. 21. Select MATERIALS, MICRO, and ASSIGN. The two models that you just put in should appear in the database list. You can assign both of them to the same material ID. Inverse Modeling

Inverse modeling allows you to use the thermal history generated by ProCAST as an input for deriving thermophysical properties, initial conditions, or boundary conditions. In order to perform the selected inverse calculations all other aspects of a problem must be set-up. This means that information about the following components of the problem must be defined. • geometry, • material properties, • interface heat transfers, • boundary conditions, • initial conditions, and • run parameters. You may use menu options in the MATERIALS, INTERFACE, BOUNDARY CONDITIONS, and RUN PARAMETERS menus to specify the component and properties to be calculated using the inverse methodology. To use the inverse method you should keep the following things in mind: 1. The inverse calculation may be performed for only one material at a time. If the material to be studied is used in more than one domain, all corresponding domains will automatically be selected. 2. The inverse calculation for the Interface may be performed in conjunction with the inverse calculation for the Boundary Condition. It may not be performed in conjunction with the inverse calculation for the material properties.


SETTING-UP PROBLEMS

3. The inverse calculation for the Boundary Condition may be performed in conjunction with the inverse calculation for the Interface. It may not be performed in conjunction with the inverse calculation for the material properties. 4. The inverse calculation may be performed, at the same time, for all film coefficient (H), flux (Q), and emissivity (E) values for one or more Heat boundary conditions. 5. In a thermophysical calculation, it is possible to determine, at the same time, specific heat, thermal conductivity, and latent heat properties. However, you must be careful that these properties are not totally independent. The diffusivity is the ratio of the thermal conductivity over the specific heat and the specific heat and the latent heat are both contained in the enthalpy. 6. The inverse calculation will converge much faster if the initial beta values (i.e., initial guesses) are closest to the final values. Therefore, you are advised to run the direct calculation with ProCAST using the initial guess before running the inverse calculation. You should check that the calculated curves generated from the results of the direct calculation are not too far from the measured curves. 7. If a property is defined as both temperature and time dependant, it is strongly advised not to perform an inverse calculation in the same time on both the temperature-dependant beta values and the time-dependant beta values. In this case, it is advisable to perform the inverse calculation with one set of beta values while keeping the others constant and then repeat the calculation vice-versa.

PAGE 2 - 12


USING PRECAST

CHAPTER 3 USING PreCAST Description

PreCAST provides the pre-simulation capability to define the problem. Setting-up the problem is the task of identifying every component of the problem, defining all of the properties which are relevant to the components of the problem, and associating properties, attributes, and conditions to each component.

Method

PreCAST runs in a either a Unix or a Microsoft Windows NT session window. PreCAST can be started using the following command line instruction at the session window prompt or the Run Dialog Window: precast {prefix} ENTER Prefix is a required parameter and you should enter the name you want given to this project. PreCAST may also be started from the EXECUTE menu in the PCS screen.

Remarks

If you start a PreCAST session without the prefix parameter shown above, you will be prompted to enter a prefix. Prior to starting PreCAST, you should change the active directory to the one which contains your project. When PreCAST is activated, it will display a work space with a gray background, the UES logo in the lower right-hand corner, and a Main Function Banner across the top of the work space. You may use the push buttons in this banner to navigate through the functions of PreCAST. These functions are: GEOMETRY, MATERIALS, INTERFACE, BOUNDARY, RADIATION, INITIAL CONDITIONS, RUN PARAMETERS, and EXIT Each of these functions are described in the following pages. They are presented in the order shown above which corresponds to their left-toright placement in the Function Banner. This also approximates the order in which you would ordinarily use the functions of PreCAST.

Related Topics

GEOMETRY, MATERIALS, INTERFACE, BOUNDARY CONDITIONS, RADIATION, INITIAL CONDITIONS, RUN PARAMETERS, EXIT

GEOMETRY USING PRECAST, PAGE 3 - 1

GEOMETRY

Description

GEOMETRY is a push button in the Main Function Banner. The GEOMETRY functions of PreCAST enable you to load or create the geometry of the part(s) or process to be modeled. These functions are also used to specify attributes of the model. Activating the GEOMETRY push button opens a menu of these geometry and model attribute functions. Selections from the menu provide capabilities which will be discussed in this section.

Method

GEOMETRY is activated by clicking on it. The initial menu is shown here. Please note that the “shaded” options on this initial menu are not available until after you have specified the UNITS or loaded a RESTART or MESHCAST file. You select other functions from this menu by clicking the desired function. The units button on this menu displays an option list from which you may select the units of length which will apply to all dimensions in the model. After specifying the UNITS you may select the appropriate Input File Option. Once you have specified the units of length or loaded a RESTART or NEUTRAL file, the initial shading of all menu options will change to gray. You may then select other functions to be performed. In most cases, when you select a function from this menu PreCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or submenus. These graphical interface tools will guide you through the process of specifying information about your model and the type of analysis to be performed. The AXISYM and VIRTUAL MOLD functions on this menu are toggle switches. In the off position the buttons are gray. In the on position these buttons are highlighted in burgundy.

PAGE 3 - 2


GEOMETRY

Remarks

Specifying the units of length: You select the desired units by clicking the UNITS push button in the menu. Clicking this button opens an Option List. Choose the desired units of length by clicking on the corresponding toggle button in the option list. When you select a unit of length, the corresponding toggle button will change color and appearance and the Option List will be closed. The choices available in this list are mutually exclusive. Selecting a second unit of length will deselect the prior selection. The units selected will be applied to all nodal coordinates read from the input file and to any points defining symmetry planes or an axis of rotation. The selection of units does not change the source data file. For RESTART and MESHCAST files, the units of length will be defined in the input file data.

Selecting the input source: PreCAST supports a broad range of input file formats. You select the input file type by clicking on the type of file you want. When you select the type of file to be loaded from the menu, you will be prompted for the file name. PreCAST will display the file prefix you entered when you started the current session of PreCAST. It will also display the appropriate suffix for the file type you have chosen. You may accept this information or you may type a different file name in the Data Input Window as shown here. When you are satisfied that the file name you want to load is entered in the Data Input Window, click on the APPLY push button to load the file or press ENTER. You may read more than one input file during a single PreCAST session by re-selecting an input file format and completing the “Selecting the input source” sequence of actions described above. You may click on the CANCEL button at any time. This will cancel the Data Input Window without loading a file.

USING PRECAST, PAGE 3 - 3

GEOMETRY

The input file types and the data types which are supported by PreCAST are described below: RESTART--typically resumes a previous PreCAST job. This option reads a previously generated prefixd.dat file. If you use the same prefix, the old prefixd.dat file will be overwritten. File suffix: d.dat MESHCAST--reads a ProCAST/MeshCAST neutral file. The format for this file is the same as the prefixd.dat file format. File suffix: d.dat PATRAN--reads a PATRAN neutral file. The following data types are handled: 1Node coordinates 2Element connectivity and material ID 8Nodal displacements (used to indicate pressure/velocity locations) 10 Nodal temperatures 16 Heat fluxes on element faces File suffix: .out IDEAS--reads an IDEAS universal file, Levels 4, 5, 6, and Master Series. The following data types are handled: 151 - Header 15 Nodal coordinates, single precision 781, 2411 - Nodal coordinates, double precision 71, 780, 2412 - Element connectivity and material ID 164 - Units 755 - Nodal temperatures 756 - Heat flux on element faces 780 - Element connectivity and material ID 781 - Nodal coordinates, double precision 782 - Heat flux on element faces File suffix: .unv ANVIL--reads an ANVIL universal file. The following data types are handled: NODE - Nodal coordinates TRIA1 - Linear triangles QUAD1 - Linear quadrilaterals TETR1 - Linear tetrahedrons PENT1 - Linear wedges HEXA1 - Linear bricks File suffix: .out ANSYS--looks for prefix.ans file and reads ANSYS files 14 and 15. PreCAST expects to find two files named prefix.14 and prefix.15. These contain element connectivity data and nodal coordinates, respectively. File suffix: .ans or .14 and .15 ARIES--reads element and node information from and ARIES geometry file. File suffix: .out

PAGE 3 - 4


GEOMETRY

When you click on the APPLY push button in the dialog box, PreCAST loads the input file and displays information about the status of that file in a message box. The following example shows a message box as a result of loading a RESTART file.

The message box provides information about: the number of elements, the number of nodes, the number of materials, a summary of the boundary conditions, and if the model contains an enclosure. When you have read the message box, click on the QUIT push button to close this message box. Related Topics

Each menu item shown above is discussed in the following pages.


GEOMETRY

GEOMETRY CREATE 2-D Description

CREATE 2-D is a push button in the GEOMETRY menu. PreCAST provides the capability to create a geometry and mesh of the part(s) or process to be modeled. Clicking on CREATE 2-D opens a simple CADtype interface. This CAD tool will allow you to draw a geometry and generate a mesh for that geometry. This 2-D geometry and mesh may then be used for further analysis.

Method

CREATE 2-D is activated by clicking on it. Selecting CREATE 2-D results in the immediate action to open a dialog box requesting you to specify the minimum and maximum X and Y coordinates for the drawing area. These values are used for scaling the input in the drawing area. To enter the values, place the cursor in the appropriate input box and type the desired value. You may move from one input box to another using the cursor or by pressing the TAB key. When you are satisfied with the values you have entered, click on the APPLY push button. This will apply the constraints to the drawing area and open the CAD tool. You may click on the CANCEL button at any time. This will cancel the dialog box and return to the GEOMETRY menu.

Remarks

The CAD capability provided in PreCAST consists of a drawing area and a toolbox. It allows you to create a geometry consisting of straight lines, arcs, and circles and generate a mesh for this geometry. The toolbox and its tools are described in the sections of this manual which are labeled: CREATE 2-D--Toolbox--Tool. Where “Tool” will be the name of the individual tool such as, LINE, ARC, RESTORE, etc.

PAGE 3 - 6


GEOMETRY

The general procedure for generating 2-D mesh for analysis consists of the following major steps: (1) Create the line drawing. Using the drawing tools in the toolbox to create the geometry. Each of these tools is discussed in the following sections. (2) Select the lines which border each region of the model. Unique region identifiers are assigned automatically. (3) Generate the mesh. In each region of the geometry, you may specify a targeted length for the mesh elements. The mesh density must be uniform within a region of the model. You may choose either a triangular or quadrilateral mesh for the entire model. (4) Smooth the mesh. Enhance the mesh by using the smooth tool until the mesh appears to be smooth. (5) Quit CREATE 2-D. Press the QUIT push button in the toolbox to exit the 2-D CAD tool. Clicking QUIT before a mesh is generated will result in creating the prefix.geom file. The mesh of triangular or quadrilateral elements of fairly uniform size is created within seconds. This allows you to obtain an overall representation of the model and/or set up problems for parametric studies very quickly. Related Topics

CREATE 2-D--Toolbox and its associated tools.


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox Description

The CREATE 2-D Toolbox is part of the 2-D drawing area which is opened as a result of clicking the APPLY push button after specifying the minimum and maximum X and Y coordinates for the drawing area in the CREATE 2-D dialog box. Some of the tools in the toolbox are push buttons which result in an immediate action such as RESTORE or SMOOTH. Other tools are toggle switches which enable or disable specific capabilities such as LINE and ARC. Still other tools are push buttons which open a dialog box to guide you in providing the specific information required to complete the selected function. An example of this last group is the MESH push button. Toolbox is displayed and available because you activated the CREATE 2-D push button in the GEOMETRY menu. The drawing area and the toolbox are shown here. You may activate a specific tool by clicking on the desired tool.

Method

To enter values in the coordinate input boxes, place the cursor in the appropriate input box and type the desired value. You may move from one input box to the other using the cursor or by pressing the TAB key. The use of these boxes is explained in the discussion of the appropriate tools.

PAGE 3 - 8


GEOMETRY

If you use the coordinate input boxes, press the ENTER key when you are satisfied with the values you have entered. This will cause the immediate execution of the function you have chosen. Remarks

You may click on the QUIT button at any time. This will cancel the CREATE 2-D screen and exit the 2-D CAD tool. Clicking QUIT before a mesh is generated will result in creating the prefix.geom file.

Related Topics

CREATE 2-D--Toolbox--Tools


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--ARC Description

The ARC tool allows you to create a single arc between two points. It is a toggle switch in the CREATE 2-D Toolbox.

Method

Select the ARC tool by clicking the ARC push button in the Toolbox. You may specify the two points by moving the cursor to the desired locations in the drawing area and clicking the left mouse button or you may type the X and Y coordinates in the coordinate input boxes. You may also use a combination of these two methods to specify the ends of the arc to be drawn. To enter values in the coordinate input boxes, place the cursor in the appropriate input box and type the desired value. You may move from one input box to the other using the cursor or by pressing the TAB key. Press the ENTER key when you are satisfied with the values you have entered. This will display the specified point in the drawing area. Repeat the input steps to provide the second point of the arc to be drawn. A RADIUS dialog box will be displayed when you have specified the two ends of the arc. You must supply the radius of the arc to be drawn and it must be greater than half the distance between the two points. Type the radius in the dialog box and press the ENTER key when you are satisfied with the value you have entered. The arc will be drawn in the drawing area.

Remarks

You may start or end an arc on an existing point in the drawing area by moving the cursor close to that point and clicking the middle mouse button. After the arc has been drawn you may reverse its orientation by clicking the REVERSE push button in the toolbox. The ARC function remains active until you select another tool from the toolbox. You may delete an arc by using the DEL LINE-ARC tool.

Related Topics

PAGE 3 - 10


DEL LINE-ARC, REVERSE

GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--CIRCLE Description

The CIRCLE tool enables you to create a full circle consisting of four arcs. CIRCLE is a push button in the CREATE 2-D toolbox. It opens an option list which allows you to choose one of two methods for creating the circle.

Method

Activate the CIRCLE function by clicking the CIRCLE push button. An option list will be displayed to give you a choice of techniques for defining where and how the circle will be drawn. These options are: CENTER-RADIUS--you specify the center point coordinates and the radius of the circle to be drawn. TWO POINTS--you specify two diametrically opposed points in the geometry. In either technique, you may specify the points by moving the cursor to the desired location in the drawing area and clicking the left mouse button or you may type the X and Y coordinates in the coordinate input boxes. You may also use a combination of these two methods. To enter values in the coordinate input boxes, place the cursor in the appropriate input box and type the desired value. You may move from one input box to the other using the cursor or by pressing the TAB key. Press the ENTER key when you are satisfied with the values you have entered. This will display the specified point in the drawing area. Repeat the input steps, as needed, to provide all required information. If you choose the CENTER-RADIUS option, a radius dialog box will be displayed. You must supply the radius of the circle to be drawn. Type the radius in the dialog box and press the ENTER key when you are satisfied with the value you have entered. The circle will be drawn in the drawing area.


GEOMETRY

Remarks

You may attach a circle to an existing point in the drawing area by moving the cursor close to that point and clicking the middle mouse button. The CIRCLE function and the option chosen will remain active until you select another tool from the toolbox. You may delete an arc or arcs by using the DEL LINE-ARC tool.

Related Topics

PAGE 3 - 12


ARC, DEL-LINE-ARC

GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--DEL LINE-ARC Description

The DEL LINE-ARC tool allows you to delete an existing line or arc. DEL LINE-ARC is a push button in the CREATE 2-D Toolbox.

Method

Select the DEL LINE-ARC tool by clicking the DEL LINE-ARC push button in the Toolbox. Move the cursor to the desired line or arc and click the left mouse button to highlight the item to be deleted. You may also select the item to be deleted by sweeping the cursor across the line or arc while holding the mouse button. A confirmation window will ask you to confirm the deletion. Click on the YES push button in the confirmation window to delete the line or arc. Clicking on the YES push button results in the immediate action to delete the line or arc. Clicking on the NO push button cancels the delete request.

Remarks

Lines or arcs are deleted one at a time. You may select another line or arc for deletion by moving the cursor to that specific line or arc and clicking the left mouse button. The deletion of lines or arcs is not reversible after you confirm the deletion. The DEL LINE-ARC function remains active until you select another tool from the toolbox.

Related Topics

ARC, LINE


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--DEL REGION Description

The DEL REGION tool allows you to delete the definition of a region in the model. DEL REGION is a push button in the CREATE 2-D Toolbox which opens a table listing all region definitions in the model.

Method

Select the region definition to be deleted by clicking on the desired definition. Selecting a region in the table will highlight the entry with a red background. At the same time, the outline of the region will change from cyan to yellow in the drawing area. Once the desired region is selected, click on the DELETE push button in the table to complete the deletion process. You may exit the DEL REGION tool by clicking the QUIT push button in the table.

Remarks

Region definitions are deleted one at a time. You may select another region definition for deletion by moving the cursor to that specific line in the table, clicking the left mouse button, and then clicking the DELETE push button. The DEL REGION function remains active until you click on the QUIT push button in the table. It is important to note that the lines, arcs, and circles associated with a region definition are not deleted or physically altered as a result of this delete operation. However, they are no longer associated with this region definition. When you create a region after you delete a region, the new region will be assigned the next sequential number. The old region numbers will not be reused. When you need to modify the drawing you must delete all regions. Only after deleting the regions will you be able to modify the geometry.

Related Topics

PAGE 3 - 14


REGION

GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--ENCLOSURE Description

The ENCLOSURE tool enables you to specify lines and arcs which will make up an enclosure rather than solid elements of the model. An enclosure may be used in a radiation problem where the enclosure may represent the furnace. The enclosure may be assigned specific properties in other components of PreCAST.

Method

Activate the ENCLOSURE function by clicking on it. The lines and arcs which define the enclosure may be selected by dragging the cursor across them while holding down the left mouse button. As a line or arc is selected it will change to red. Once a line or arc has been selected release the mouse button. The letter E will be displayed at the midpoint of each line/arc in the enclosure. Continue selecting lines and/or arcs until the enclosure has been fully described.

Remarks

The ENCLOSURE function remains active until you select another tool from the toolbox. All enclosure selections should be done at the same time. An enclosure is used for radiation view calculations.

Related Topics

NONE


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--LINE Description

The LINE tool allows you to create a single line or a series of connected lines. It is a toggle switch in the CREATE 2-D Toolbox.

Method

Select the LINE tool by clicking the LINE push button in the Toolbox. You may specify the two end points for a line by moving the cursor to the desired locations in the drawing area and clicking the left mouse button or you may type the X and Y coordinates in the coordinate input boxes. You may also use a combination of these two methods to specify the ends of the line to be drawn. To enter values in the coordinate input boxes, place the cursor in the appropriate input box and type the desired value. You may move from one input box to the other using the cursor or by pressing the TAB key. Press the ENTER key when you are satisfied with the values you have entered. A coordinate point, represented by a small green square, will be drawn indicating the presence of the line point. Repeat the input steps to provide the second point of the line to be drawn. To draw continuous lines, move the cursor to each desired point and click the left mouse button. It is important to note that you must re-select the LINE tool in the Toolbox to terminate the continuous lines and allow you to draw another line or another set of continuous lines. You may start or end a line on an existing point in the drawing area by moving the cursor close to that point and clicking the middle mouse button.

Remarks

You may delete an arc by using the DEL LINE-ARC tool. Related Topics

PAGE 3 - 16


DEL LINE-ARC

GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--MESH Description

MESH is a push button in the CREATE 2-D toolbox. It opens a table of element dimensions.

Method

Activate the MESH function by clicking the MESH push button. The table of element dimensions will be opened overlaying a portion of the toolbox. This table will list each region of the model. You may specify the target length for the mesh elements in a specific region of the model. If two regions adjoin each other and have different lengths for the mesh elements, the finer mesh density will be used along the common edges. To specify a length value, click on the desired table entry. The background of the selected table entry will change to red. At the same time, the corresponding region of the model will be highlighted in yellow in the drawing area. In the Edit Value input box, type the length you want PreCAST to use as the target length for elements in this region of the model. When you are satisfied with the value entered, press the ENTER key. This will update the table entry and the next region in sequence will be highlighted. When you are satisfied with all table entries, click on the GEN MESH push button in the table. This will open an option list which will allow you to choose the type, triangular or quadrilateral, of mesh which will be generated. Indicate your choice by moving the cursor over the desired mesh type and click the left mouse button. This will result in the immediate generation of the mesh.


GEOMETRY

Remarks

Clicking on QUIT before a mesh is generated will result in creating the prefix.geom file. The time required to create the mesh depends on the element size relative to the region, but is normally finished within a minute. While the mesh is being generated, PreCAST displays a progress meter in the lower portion of the drawing area. When the mesh has been generated it will be displayed in the drawing area, as shown here.

Note the two densities of mesh which were generated. These were based upon the values in the table as described above. CREATE 2-D can not generate any higher order mesh elements such as quadratic. Related Topics

PAGE 3 - 18


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--MOVE Description

The MOVE tool allows you to move an existing point in the drawing area. MOVE is a toggle button in the CREATE 2-D Toolbox. Lines connected to the point which is moved will also be moved to maintain their contact with the selected point.

Method

Activate the MOVE function by clicking the MOVE push button. The cursor icon will change to resemble a small bulls eye. Move the cursor to the point you want to move and click either the left or the middle mouse button. Move the cursor to the desired new location and click the left or middle mouse button again.

Remarks

The MOVE function remains active until you select another tool from the toolbox. MOVE will not work on points which are connected to arcs or points which have been assigned to regions.

Related Topics

LINE, ARC


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--QUIT Description

QUIT closes the CREATE 2-D drawing area and toolbox.QUIT is a push button in the CREATE 2-D toolbox and results in an immediate action.

Method

Activate QUIT by clicking on it.

Remarks

If you press QUIT before a mesh has been generated it will be saved in a prefix.geom file. Clicking QUIT before a mesh is generated will result in creating the prefix.geom file. The CREATE 2-D drawing area will be closed and the meshed geometry will be displayed in the work window pane.

Related Topics

PAGE 3 - 20


MESH

GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--REGION Description

The REGION tool enables you to assign lines and arcs to specific regions of the model. These lines and arcs define the boundaries of a region. A region may be assigned a specific material ID and other properties in other components of PreCAST.

Method

Activate the REGION function by clicking the REGION push button. The lines and arcs which form the border of the region may be selected by dragging the cursor across them while holding down the left mouse button. As a line or arc is selected it will change to red. Once a line or arc has been selected release the mouse button. You may select lines and arcs which make up internal boundaries in the same manner.

Remarks

Continue selecting lines and/or arcs until the region has been fully enclosed. At that time, a region number will be automatically assigned. These numbers will be displayed at the midpoint of each line/arc in the region. You should include any inner borders of a region in that region’s selection. For example, if you were modeling a donut in 2-D, the region of the donut would include the arcs forming the outside of the donut and the arcs forming the outside of the donut hole. Click on the REGION push button again to select lines and arcs to be assigned to another region. Individual lines or arcs may be associated with more than one region.

Related Topics

DEL REGION


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--RESTORE Description

The RESTORE tool reads a 2-D geometry which has previously been saved as a prefix.geom file. RESTORE is a push button in the CREATE 2-D Toolbox which results in the immediate operation to read the prefix.geom file and display the geometry in the drawing area.

Method

Activate the RESTORE function by clicking on it. You may use any arbitrary numbers to define the workspace. The model will automatically scale the work area.

Remarks

Prefix.geom files are created when you select the MESH tool or when you QUIT CREATE 2-D.

Related Topics

MESH, QUIT

PAGE 3 - 22


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--REVERSE Description

The REVERSE tool allows you to switch the orientation of the last arc created. As a result of the REVERSE tool’s action a concave arc can be made convex and vice versa. REVERSE is a toggle switch in the CREATE 2-D Toolbox.

Method

Select the REVERSE tool by clicking the REVERSE push button in the Toolbox. Clicking the REVERSE push button results in the immediate action to change the orientation of the arc.

Remarks

Clicking the REVERSE push button again will change the arc’s orientation back to its original position. You may click on the REVERSE push button at any time, however, it will always change the orientation of the last arc you have drawn.

Related Topics

ARC


GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--SPLIT Description

The SPLIT tool enables you to create a new point at the intersection of two lines or arcs. SPLIT is a push button in the CREATE 2-D toolbox.

Method

Activate the SPLIT function by clicking the SPLIT push button. Move the cursor across the desired intersection while holding down the left mouse button. The two lines to be selected will change to yellow when they have been selected. Release the mouse button and the new point will appear.

Remarks

You may split a line or arc in order to be able to remove either of the resulting segments. The SPLIT function remains active until you select another tool from the toolbox.

Related Topics

PAGE 3 - 24


ARC, LINE, DEL LINE-ARC

GEOMETRY

GEOMETRY CREATE 2-D--Toolbox--SMOOTH Description

The SMOOTH tool enables you to improve the quality of the mesh. SMOOTH is a push button in the CREATE 2-D toolbox.

Method

Activate the SMOOTH function by clicking the SMOOTH push button. This results in the immediate action of improving the quality of the mesh. The improved mesh will be displayed in the drawing area.

Remarks

SMOOTH improves the shape of the triangular or quadrilateral elements in the mesh by adjusting the nodal locations. Each node is placed at the center of the nodes immediately surrounding it. The SMOOTH push button may be pressed several times until no adjustment is detectable in the drawing area.

Related Topics

MESH


GEOMETRY

GEOMETRY SYMMETRY Description

SYMMETRY is a push button in the GEOMETRY menu. PreCAST provides the capability to specify rotational and/or mirror symmetry for radiation problems. SYMMETRY opens an option list sub-menu which allows you to specify the symmetry properties for your model.

Method

Activate SYMMETRY by clicking the SYMMETRY push button. This results in an immediate action to open the sub-menu shown here. The method and syntax for each of these options will be described below. Each one may be activated by clicking the left mouse button when the cursor is over the respective push button. ROTATIONAL--specifies a symmetry in which a base object is repeated, at evenly spaced intervals, around an axis of rotation. Activating the ROTATIONAL option will open a dialog box as shown.

In this dialog box you specify: SECTORS--specifies the number of times the base object is to be repeated around the axis of rotation. Enter an integer value. COORDINATES0 --one of two sets of coordinates which define the axis of rotation. COORDINATES1 --one of two sets of coordinates which define the axis of rotation. When you are satisfied with the values entered in the dialog box, click on the APPLY push button. You may click on the CANCEL push button at any time to cancel this operation without setting or changing any values.

PAGE 3 - 26


GEOMETRY

MIRROR 1--specifies a symmetry in which a plane of symmetry is used to create a mirror image about the specified plane. Activating the MIRROR 1 option will open a dialog box as shown.

In this dialog box you specify the coordinates of the three points required to define a plane: COORDINATES0 --one of three sets of coordinates which define the plane of symmetry. COORDINATES1 --one of three sets of coordinates which define the plane of symmetry. COORDINATES2 --one of three sets of coordinates which define the plane of symmetry. When you are satisfied with the values entered in the dialog box, click on the APPLY push button. You may click on the CANCEL push button at any time to cancel this operation without setting or changing any values. MIRROR 2--works in the same way as MIRROR 1 and allows you to create two planes of mirror symmetry in the same problem. EXECUTE--finds faces on the model which lie on the planes of symmetry and includes them in a symmetry boundary condition set. QUIT--closes the option list box. Remarks

You may have one rotational symmetry and two planes of mirror symmetry in the same problem. If there is only one plane of symmetry, then you should input the data in MIRROR 1. The symmetry properties are used for creating virtual images of an object which will take part in the view factor calculations.

Related Topics


GEOMETRY

GEOMETRY GRAVITY Description

GRAVITY is a push button in the GEOMETRY menu. PreCAST provides the capability to specify the direction of gravitational pull on the model. GRAVITY opens a dialog box which allows you to specify the direction and units of measure for the gravitational factors affecting your analysis. This is used in fluids and stress simulation problems.

Method

Activate the GRAVITY function by clicking the GRAVITY push button. This results in an immediate action displaying the dialog box shown here. The dialog box also contains push buttons which may be used to activate additional gravity-related functions. The method and syntax for each of these functions and input options will be described below. Each one may be activated by clicking the left mouse button when the cursor is over the respective push button. X, Y and Z--are the components of the gravitational vector. To enter the values, place the cursor in the appropriate input box and type the desired value. You may move from one input box to another using the cursor or by pressing the TAB key. For example, in SI units, gravitational acceleration at the earth’s surface is 9.8 meters/second2 in the downward direction. If the Z axis in your model is pointing up, you would enter -9.8 for the Z component and leave the X and Y components at 0.0. The default values for these components, in a 2-D problem are: X = 0.0, Y = -9.8, and Z = 0.0. The default values in a 3-D problem depend upon the model. If the direction of gravity is at an angle, you must manually calculate the x, y, and z component of the gravitational force.

PAGE 3 - 28


GEOMETRY

UNITS--specifies the units of gravitational acceleration to be used for this analysis. This push button is a rotary toggle switch. Clicking on the UNITS toggle switch will cycle through the optional units of acceleration. Your choices are: {m/sec**2|cm/sec**2|mm/sec**2|ft/sec**2|in/sec**2}. The default is m/sec**2. When you are satisfied with the values you have entered, click on the APPLY push button. ROTATE--enables you to specify an axis of rotation and the angle of rotation as a function of time. Activating the ROTATE option will open the dialog boxes shown below.

AXIS OF ROTATION--use the dialog box to specify: COORDINATES0 --one of two sets of coordinates which define the axis of rotation. COORDINATES1 --one of two sets of coordinates which define the axis of rotation. ANGLE VERSUS TIME FUNCTION--is defined in a dialog box which is a two column table. In column one (Time) you specify the elapsed time. In column two (Theta) you specify the corresponding amount of rotation in degrees. At the top of column one in the table is a rotary toggle button which may be used to set the units of time for the table. Your choices for this unit of time are: {sec|min}. Successive clicks on this push button will toggle between these two units. The default is sec.


GEOMETRY

To enter values in the table: (1) move the cursor to a position to the right of the number one, (2) click on the left mouse button. The first row and column space will be highlighted in red. (3) move the cursor to the Edit Value input box at the bottom of the table, (4) enter the desired value, (5) press ENTER. The entered value will be placed in the table and the cursor will automatically be moved to the next available column and row entry. (6) Continue entering data as necessary by repeating steps 4 and 5. You should have a minimum of two table entries. To change values in a table entry: (1) move the cursor to the table entry to be changed, (2) click on the left mouse button. The table entry will be highlighted in red and its value will be displayed in the Edit Value input box. (3) move the cursor to the Edit Value input box at the bottom of the table, (4) enter the desired value, (5) press ENTER. The entered value will be placed in the table and the cursor will automatically be moved to the next available column and row entry. SAVE--When you are satisfied with the values entered in the table, click on the SAVE push button at the top of the table. This results in the immediate action to save the Angle Versus Time Function table.

PAGE 3 - 30


GEOMETRY

GRAPH--This push button results in the immediate action to display a graph of the values in the Angle Versus Time Function table. The following example is based upon table data which was created for convenience of illustration.

ERASE--this push button results in the immediate action to erase the entire contents of the Angle Versus Time Function Table. QUIT--this push button results in closing the Angle Versus Time Function dialog box. The dialog boxes are closed without saving any data which may have been entered or changed. If you want to retain the data in the table, be sure to click on the SAVE push button prior to using QUIT. CANCEL--You may click on the CANCEL push button at any time to close the GRAVITY function dialog boxes. This CANCEL operation does not save or store any values. APPLY--when you are satisfied with the values entered in the dialog boxes, click on the APPLY push button. This results in the immediate action to save the values you entered as a part of this analysis. Remarks

The ROTATE capability of GRAVITY is typically used for tilt pouring operations.

Related Topics


GEOMETRY

GEOMETRY CENTRIFUGAL Description

CENTRIFUGAL is a push button in the GEOMETRY menu. It opens a dialog box which allows you to specify an axis of rotation and an angular velocity for your analysis. This is used in centrifugal casting process problems.

Method

Activate the CENTRIFUGAL function by clicking the CENTRIFUGAL push button. This results in an immediate action to open the dialog box and control panel shown here. The control panel contains push buttons which may be used to specify angular velocity. The method and syntax for each of these functions and input options will be described below. Each one may be activated by clicking the left mouse button when the cursor is over the respective push button. In the dialog box, you enter the coordinates which describe the axis of rotation. COORDINATES0 --one of two sets of coordinates which define the axis of rotation. COORDINATES1 --one of two sets of coordinates which define the axis of rotation. To enter the values, place the cursor in the appropriate input box and type the desired value. You may move from one input box to another using the cursor or by pressing the TAB key.

PAGE 3 - 32


GEOMETRY

CONSTANT--specifies a constant rate of rotation about the axis of rotation. This push button opens a dialog box which allows you to enter the constant and select the time interval units. Enter the constant rate of rotation in radians. At the top right-hand corner of the dialog box is a rotary toggle button which may be used to set the time interval units. Your choices for this unit of time are: {1/sec|1/min}. Successive clicks on this push button will toggle between these two values. The default is 1/sec. TIME--enables you to specify an angular velocity which is a function of time. When you click on the TIME push button a table will open. You use this table to specify the time and angular velocities for your analysis. At the top of column one of this two-column table is a rotary toggle button which may be used to set the units of time for the table. Your choices for this unit of time are: {sec|min}. Successive clicks on this push button will toggle between these two units. The default is sec. At the top of column two is a rotary toggle button which may be used to set the units of time angular velocity for the table. Your choices for this unit of time are: {1/sec|1/min}. Successive clicks on this push button will toggle between these two values. The default is 1/sec. In column one you specify the elapsed time. In column two you specify the corresponding angular velocity in radians. To enter values in the table: (1) move the cursor to a position to the right of the number one, (2) click on the left mouse button. The first row and column space will be highlighted in red. (3) move the cursor to the Edit Value input box at the bottom of the table, (4) enter the desired value,


GEOMETRY

(5) press ENTER. The entered value will be placed in the table and the cursor will automatically be moved to the next available column and row entry. (6) Continue entering data as necessary by repeating steps 4 and 5. You must have at least two table entries. To change values in a table entry: (1) move the cursor to the table entry to be changed, (2) click on the left mouse button. The table entry will be highlighted in red and its value will be displayed in the Edit Value input box. (3) move the cursor to the Edit Value input box at the bottom of the table, (4) enter the desired value, (5) press ENTER. The entered value will be placed in the table and the cursor will automatically be moved to the next available column and row entry. SAVE--When you are satisfied with the values entered in the table, click on the SAVE push button at the top of the table. This results in the immediate action to save the table. GRAPH--This push button results in the immediate action to display a graph of the values in the table. The following example is based upon table data which was created for convenience of illustration.

ERASE--this push button results in the immediate action to erase the entire contents of the table.

PAGE 3 - 34


GEOMETRY

QUIT--this push button results in closing the Time and Angular Velocity dialog boxes. The dialog boxes are closed without saving any data which may have been entered or changed. If you want to retain the data in the table, be sure to click on the SAVE push button prior to using QUIT. CANCEL--You may click on the CANCEL push button at any time to close the GRAVITY function dialog boxes. This CANCEL operation does not save or store any values. APPLY--when you are satisfied with the values entered in the dialog boxes, click on the APPLY push button. This results in the immediate action to save the values you entered as a part of this analysis. Remarks

ProCAST multiplies the CONSTANT value supplied times the Tabular entries in the TIME/VELOCITY table, if any, to determine the angular velocity.

Related Topics


GEOMETRY

GEOMETRY CHECK GEOM Description

CHECK GEOM is a push button in the GEOMETRY menu. CHECK GEOM opens an option list sub-menu. PreCAST provides the capability to verify that all mesh elements have positive Jacobians, that all surface elements have positive surface areas, and that all enclosure elements have normals with the proper orientation. These checks are important to further successful analysis of your model.

Method

Activate the CHECK GEOM function by clicking the CHECK GEOM push button. This results in an immediate action to open the option list sub-menu shown here. The option list provides the capability to examine specific aspects of your model. The option list is a series of push buttons corresponding to the type of check which will be performed. The method and syntax for each of these options will be described below. Each one may be activated by clicking the left mouse button when the cursor is over the respective push button. NEG--JAC: checks the model to make sure that all elements in the model have positive Jacobians. Elements with negative Jacobian values are identified in a list. The list is displayed on the right side of the work window pane. An example of the list is shown here. To display negative Jacobian elements graphically in the work window pane, select an element number and click on the SHOW ELEMENT push button. NEG-AREA: checks the model to make sure that all surface elements in the model have positive surface areas. Elements with negative areas are identified in a list. The list is displayed on the right side of the work window pane and the negative surface areas are displayed graphically in the work window pane. The list will be similar to the one shown above for NEG-JAC elements. This test is only significant for radiation models. View factors cannot be calculated for faces

PAGE 3 - 36


GEOMETRY

that fail this test. ENCLOSURE: checks the model to make sure that all of the enclosure elements have normals with the proper orientation. Normal orientation of all the enclosure elements is displayed graphically in the work window pane. Additionally, five tools will

Tools for manipulating the orientation of the enclosure’s normals.

These arrows indicate the direction of the enclosure’s normals.

be displayed in the right margin. These tools allow you to select specific enclosure elements and change the direction of their normals. These tools are shown here and explained in the following paragraphs.


GEOMETRY

SELECT: allows you to select individual elements for manipulation. To activate this tool, click on the SELECT push button. You may then choose the element(s) by placing the cursor over them and

selecting them by pressing the left mouse button or you may drag a selection box by pressing the right mouse button and enclosing the desired elements. When the elements have been selected they will change color to red. In the example shown here, elements have been selected. DESELECT: allows you to deselect individual elements for manipulation. To activate this tool, click on the DESELECT push button. You may then choose the element(s) by placing the cursor over them and snagging them while pressing the left mouse button or you may drag a selection box by pressing the right mouse button and enclosing the desired elements. When the elements have been deselected they will change color to white. SELECT ALL: allows you to select all elements for manipulation. To activate this tool, click on the SELECT ALL push button. When the elements have been selected they will change color to red.

PAGE 3 - 38


GEOMETRY

CANCEL: allows you to close the enclosure display. To activate this option, click on the CANCEL push button. This will result in the immediate action to close the enclosure display. REVERSE: allows you to reverse the direction of the normals for the selected elements. To activate this tool, click on

the REVERSE push button. This will result in the immediate action to change the direction of all and only the elements which have been selected. For convenience of illustration, in the figure shown here, three elements have had the direction of their normals reversed.


GEOMETRY

VOLUMES: calculates the volume of each material region. The calculation will be in cubic centimeters. These material volumes will be displayed in a table at the right-side of the work window pane. An example of the table of material volumes is shown here.

These diagnostic tools should be used to evaluate the quality of the geometry and mesh. The quality of the geometry and mesh have a direct bearing upon the eventual outcome of the simulation.

Remarks

Related Topics

PAGE 3 - 40


GEOMETRY

GEOMETRY AXISYM Description

AXISYM is a toggle button in the GEOMETRY menu. AXISYM allows you to specify the Y axis as the axis of symmetry. PreCAST provides the capability to model 2-D axisymmetric problems.

Method

Activate the AXISYM toggle button by clicking the AXISYM push button. This results in an immediate action to change the color of the status box. Subsequent clicks on the AXISYM push button will toggle between turning axisymmetry on and off.

Remarks

When AXISYM is toggled to the “on” position, the Y axis is always taken as an axis of symmetry and the X axis will point in the positive radial direction. You must have your model aligned at X = 0 for AXISYM to work.

Related Topics


GEOMETRY

GEOMETRY VIRTUAL MOLD Description

VIRTUAL MOLD is a push button in the GEOMETRY menu. PreCAST provides the capability to simulate a mold around the casting without creating a geometry for the mold. This allows you to analyze the heat conduction around the casting by mimicking the effect of a real mold.

Method

Activate the VIRTUAL MOLD function by clicking the VIRTUAL MOLD push button. This results in an immediate action to open a dialog box which enables you to enter the minimum and maximum coordinates of the mold. The color of the status box will also change. As shown here, the dialog box consists of input lines where you may specify the minimum and maximum values for each of the x, y, and z coordinates of the mold. The dialog box also contains three push buttons which perform the specific actions described below. Each one may be activated by clicking the respective push button. APPLY: applies the minimum and maximum values entered, creates the virtual mold, and closes the dialog box. REMOVE: removes the coordinate values entered and closes the dialog box. It also removes the virtual mold if it has been created. CANCEL: closes the dialog box.

PAGE 3 - 42


GEOMETRY

Remarks

VIRTUAL MOLD applies an analytical heat conduction solution around the casting which mimics the effect of a real mold. When minimum and maximum coordinates have been specified and applied, Pro-CAST computes a penetration depth for each face of the casting that is within the “virtual” box. VIRTUAL MOLD adds a new material ID to the model. You may assign mold properties to this new material ID. Using the Interface component of ProCAST, you may create and assign interface heat transfer coefficients between the external faces of the casting and the virtual mold. The color legend, as shown in this figure, graphically represents the resulting thermal depth or penetration depths between the virtual mold and the casting.

Related Topics

INTERFACE


MATERIALS

MATERIALS Description

MATERIALS is a push button in the Main Function Banner. This function of PreCAST enables you to add materials and your own material properties to the database. It also enables you to assign specific materials to the model. When you activate the MATERIALS push button, a menu is opened which will allow you to work with specific properties for each material in the database. Selections from the menu provide capabilities which will be discussed in this section.

Method

MATERIALS is activated by clicking on it. The initial menu is shown here. When you select a function from this menu PreCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting information about the materials in the database. You may leave the MATERIALS function by clicking another push button in the Main Function Banner.

Remarks

ProCAST provides the capability and flexibility to add, delete, or modify a material in the material database. If you intend to use the material data that comes with ProCAST, as is, you can proceed to the ASSIGN function. The major capabilities of the MATERIALS function of PreCAST will be summarized here. Each capability will be described in greater detail in this manual. DATABASE Provides the data management functions for the materials and their respective properties in your database. DATABASE allows you to add, delete, copy, and modify entries in the materials database. ASSIGN Provides the capability to assign material properties to elements in the model. STRESS Provides the data management and assign functions for stress modeling material properties. Allows you to define a mechanical model for the material. MICRO

PAGE 3 - 44


MATERIALS

Provides the data management and assign functions for micro modeling material properties. INVERSE Inverse modeling will calculate selected material properties by using the numerically generated thermal history and measured temperatures. The inverse solver calculates the optimum material property which will give the best match between the measured and calculated cooling curves for the material. The properties which may be determined using inverse modeling are: Heat capacity, Thermal conductivity, and Latent heat. When you select the STRESS or MICRO capabilities, another submenu will be displayed. From this sub-menu you may select the DATABASE or ASSIGN functions relating to either the stress or micro properties of the material. ProCAST’s graphical user interface provides a straight forward and simple procedure for working with the various databases used by ProCAST. This database facility is described elsewhere in this manual. You should read about this facility before attempting to modify the materials database. Related Topics

DATABASE FACILITY, REGION


MATERIALS

MATERIALS DATABASE Description

DATABASE is a push button in the MATERIALS menu which accesses the Materials Database. Using ProCAST’s DATABASE FACILITY you may create, delete, or modify a material or its properties in the materials database. These materials may then be used for simulation and analysis.

Method

DATABASE is activated by clicking on it. This results in the immediate action to display a table containing any materials which may be in the database. The figure shown here illustrates a display of the materials in the Material Database. PreCAST allows you to Read, Add, Copy, and Delete materials from the Materials Database. These capabilities are described in the DATABASE FACILITY section of this manual. You should also refer to the TABLE MAINTENANCE section of this manual which describes ProCAST’s graphical interface for maintaining tables. This section will discuss the requirements for adding a material to the database and how you specify individual properties and attributes for that material. To add a material to the database, click on the ADD push button in the Material Database display. This will result in the immediate action to open a blank Material Description which is shown below. Note that PreCAST has entered the USER name and the DATE for you.

PAGE 3 - 46


MATERIALS

The minimum requirement for adding a material to the database is to give it a name and specify properties for the material. Individual properties which may be required depend upon the type of modeling and analysis to be done. The syntax and options available for the Material Definition are discussed below. MATERIAL NAME: Enter the name you want to give the new material. The material name must begin with an alphabetic character and may include upper and lower case characters. BASE: ProCAST will calculate material properties based upon the material database which is supplied with it. To enter a base material, place the cursor in the BASE input box and type one of the material types supplied. You may choose from [ Al | Ni | Ti | Fe]. When you have typed the base material to be used, click on the COMPOSITION push button.


MATERIALS

COMPOSITION: This push button allows you to specify the alloy composition to have ProCAST calculate the material properties. As shown below, when you select this push button, a composition table will be displayed. In this table you may enter the components of the alloy and their weight percentage of the total alloy. To enter the components of the alloy, place the cursor in the first available input space in column one and type the element’s symbol. Then place the cursor in the column two input space adjacent to the element and type the percentage of this element which is in the compound. You may repeat this process for additional elements. You may change an alloy or its corresponding percentage by placing the cursor in the desired input line and re-typing the desired value. When you are satisfied with the composition, click on the APPLY push button. The composition will be highlighted as a reminder that data has been entered. You may close the composition table, without specifying the alloy composition, by clicking the CANCEL push button. In the input box labeled BASE, enter the base element of the alloy.

PAGE 3 - 48


MATERIALS

PROPERTIES: Properties are shown in four categories: THERMAL, FLUID, FILTER, and ELECTROMAGNETIC. The properties which may be chosen within each category are displayed as a group of check boxes or push buttons. To specify a property, click the left mouse button when the cursor is over the desired property’s check box. Selecting a property in this manner will result in the immediate action to display an additional dialog box or data input table. Some properties may be described only as a constant value while others may be described as a constant, a linear function or a quadratic function. Based upon the individual property you select, ProCAST will display the appropriate dialog or input table. The simplest of these input boxes is similar to the one shown here and may contain a rotary toggle switch for the units of measure and a text input line. Select the desired units of measure by clicking on the UNITS push button. Successive clicks on this push button will toggle through the available options. To enter the desired value for this property or attribute move the cursor to the text input line and type the value. When you click on the APPLY push button, the data entered will be stored, the dialog box will be closed, and the property’s check box on the Material Definition display will be highlighted in light blue. You may click on the CANCEL push button to close the dialog box without saving the data. For those properties which may also be described as linear or quadratic functions, ProCAST will display an option box from which you may choose to use a CONSTANT, LINEAR, or QUADRATIC function. An example of this option box is shown here. Selecting the CONSTANT option will display a dialog box similar to the one described in the preceding paragraphs. Selecting the LINEAR option will result in the immediate action to display an input table. This table, like the dialog box for a constant, may contain rotary toggle switches for the units of measure. As shown in this example for Conductivity, there are two toggle switches which also serve as the column sub-headings for the table.


MATERIALS

Select the desired units of measure by clicking on the column heading push buttons. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and Rotary Toggle Switches press the ENTER key. This will place the value in the table and move the cursor to the next available table entry. When you are satisfied with the table entries, click on the STORE push button, the data in the table will be stored, the dialog box will be closed, and the property’s check box on the Material Definition display will be highlighted in light blue. You may click on the GRAPH push button to display a graph of the function. You may click on the ERASE push button to erase the entire contents of the table. You may click on the CANCEL push button to close the dialog box without saving the data. Selecting the QUADRATIC option will result in the immediate action to display an input table. In this table, column sub-headings may act like the rotary toggle switches for the units of measure. As shown in the following example, there are two column subheading toggle switches. Select the desired PAGE 3 - 50


MATERIALS

units of measure by clicking on the column sub-heading push buttons. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and press the ENTER key. This will place the value in the table and move the cursor to the next available table entry. When you are satisfied with the table entries, click on the STORE push button, the table data will be stored, the dialog box will be closed and the property’s check box on the Material Definition display will be highlighted in light blue. The GRAPH, ERASE, and CANCEL push buttons function in the same way as described in the paragraphs above. The syntax options for Material Properties will be presented below. THERMAL PROPERTIES CONDUCTIVITY--may be specified as a constant, a linear function or a quadratic function. Constant: Select the units from the following choices: {W/m/K | cal/cm/C/sec | Btu/ft/F/sec | cal/cm/C/min | Btu/ft/F/min | cal/mm/C/sec | Btu/in/F/sec | Btu/in/F/min} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Conductivity units from: {W/m/K | cal/cm/C/sec | Btu/ft/F/sec | cal/cm/C/min | Btu/ft/F/min | cal/mm/C/sec | Btu/in/F/sec | Btu/in/F/min} Enter the temperatures in column one and Conductivity values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Conductivity units from: {W/m/K | cal/cm/C/sec | Btu/ft/F/sec | cal/cm/C/min | Btu/ft/F/min | cal/mm/C/sec | Btu/in/F/sec | Btu/in/F/min} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four. DENSITY--may be specified as a constant, a linear function or a quadratic function. Constant: Select the units from the following choices: {kg/m**3 USING PRECAST, PAGE 3 - 51

MATERIALS

| g/cc | g/mm**3 | lb/ft**3 | lb/in**3} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Density units from: {kg/m**3 | g/cc | g/mm**3 | lb/ft**3 | lb/in**3} Enter the temperatures in column one and Density values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Density units from: {k/m**3 | g/cc | g/mm**3 | lb/ft**3 | lb/in**3} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four.

PAGE 3 - 52


MATERIALS

SPECIFIC HEAT--may be specified as a constant, a linear function or a quadratic function. Constant: Select the units from the following choices: {kJ/kg/K | cal/g/C | Btu/lb/F} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Specific Heat units from: {kJ/kg/K | cal/g/C | Btu/lb/F} Enter the temperatures in column one and Specific Heat values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Specific Heat units from: {kJ/kg/K | cal/g/C | Btu/lb/F} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four. ENTHALPY--may be specified as a linear function or a quadratic function. Linear function: Select the Temperature from: {C | F | R | K} Select the Enthalpy units from: {kJ/kg | cal/g | Btu/lb} Enter the temperatures in column one and Enthalpy values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Enthalpy units from: {kJ/kg | cal/g | Btu/lb} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four.


MATERIALS

FRACTION SOLID--may be specified as a linear function or a quadratic function. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Fraction Solid values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four. CALC SOLID PATH--this push button results in the immediate action to open a sub-menu which allows you to choose either SCHEIL or LEVER. As shown here, this submenu consists of two push buttons. Note: The CALC SOLID PATH capability will not be implemented until a release of ProCAST subsequent to 3.1.0. SOLIDUS--is specified as a constant. Constant: Select the Temperature from: {C | F | R | K} Enter the constant value to be used in the Edit Value input line. LIQUIDUS--is specified as a constant. Constant: Select the Temperature from: {C | F | R | K} Enter the constant value to be used in the Edit Value input line. LATENT HEAT--is specified as a constant. Constant: Select the units from: {kJ/kg | cal/g | Btu/lb} Enter the constant value to be used in the Edit Value input line.

PAGE 3 - 54


MATERIALS

FLUID PROPERTIES VISCOSITY may be specified as Newtonian or Non-Newtonian. When you select the VISCOSIT Y property check box, an option menu will be displayed. As shown in this figure, the option menu consists of two push buttons. NEWTONIAN--Select Newtonian by clicking the NEWTONIAN push button. This will display an option menu from which you may elect to describe the material’s viscosity as a constant, linear function or quadratic function. Constant: Select the units from the following choices: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Viscosity units from: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the temperatures in column one and Viscosity values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Viscosity units from: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four.


MATERIALS

CARREAU-YASUDA--Select Carreau-Yasuda by clicking on it. This will display a menu which will allow you to describe the viscosity. This menu is shown here. You select the method by clicking the desired method’s push button. Non-Newtonian values may be described as constants or as linear functions. This method is described in Equation C.7.2 in Appendix C.

ZERO VISCOSITY Constant: Select the units from the following choices: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Viscosity units from: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the temperatures in column one and Viscosity values in column two. INFINITE VISCOSITY Constant: Select the units from the following choices: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Viscosity units from: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the temperatures in column one and Viscosity values in column two.

PAGE 3 - 56


MATERIALS

PHASE SHIFT Constant: The units are sec/min Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} The Viscosity units are sec/min Enter the temperatures in column one and Viscosity values in column two. POWER Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Viscosity values in column two. YASUDA Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Viscosity values in column two.


MATERIALS

POWER-CUTOFF--Select Power-Cutoff by clicking on it. This will display a menu which will allow you to describe the viscosity. This menu is shown here. You select the method by clicking the on the desired method’s push button. Power-Cutoff values may be described as constants or as linear functions.

ZERO VISCOSITY Constant: Select the units from the following choices: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Viscosity units from: {Pa.s | N.s/m**2 | centipoise | poise | lb/s/ft | lb/min/ft | lb/hr/ft} Enter the temperatures in column one and Viscosity values in column two. K FACTOR Constant: Select the units from the following choices: {sec | min} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Phase Shift units from: {sec | min} Enter the temperatures in column one and Phase Shift values in column two.

PAGE 3 - 58


MATERIALS

POWER Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Power values in column two. SURFACE TENSION--may be specified as a constant, a linear function or a quadratic function. Constant: Select the units from the following choices: {N/m | dyne/cm | lb/ft | lb/in} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Surface Tension units from: {N/m | dyne/cm | lb/ft | lb/in} Enter the temperatures in column one and Surface Tension values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Surface Tension units from: {N/m | dyne/cm | lb/ft | lb/in} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four.


MATERIALS

PERMEABILITY--may be specified as a constant, a linear function or a quadratic function. If you provide this data, it will override permeability data developed internally by ProCAST. Constant: Select the units from the following choices: {m**2 | cm**2 | mm**2 | ft**2 | in**2} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Permeability units from: {m**2 | cm**2 | mm**2 | ft**2 | in**2} Enter the temperatures in column one and Permeability values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Permeability units from: {m**2 | cm**2 | mm**2 | ft**2 | in**2} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four. FILTER PROPERTIES VOID FRACTION--is specified as a constant. Constant: Enter the constant value to be used in the Edit Value input line. SURFACE AREA--is specified as a constant. This specifies the surface area to volume ratio. Constant: Select the units from: {1/m | 1/cm | 1/mm | 1/ft | 1/in} Enter the constant value to be used in the Edit Value input line.

PAGE 3 - 60


MATERIALS

ELECTROMAGNETIC PROPERTIES PERMEABILITY--refers to magnetic permeability and may be specified as a constant, a linear function or a quadratic function. Constant: Select the units from the following choices: {henry/m | henry/cm | henry/mm | henry/ft | henry/in} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Permeability units from: {henry/m | henry/cm | henry/mm | henry/ft | henry/in} Enter the temperatures in column one and Permeability values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Permeability units from: {henry/m | henry/cm | henry/mm | henry/ft | henry/in} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four.


MATERIALS

CONDUCTIVITY–refers to electrical conductivity and may be specified as a constant, a linear function or a quadratic function. Constant: Select the units from the following choices: {ohm-m | ohm-cm | ohm-mm | ohm-ft | ohm-in} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Conductivity units from: {ohm-m | ohm-cm | ohm-mm | ohm-ft | ohm-in} Enter the temperatures in column one and Conductivity values in column two. Quadratic function: Select the Temperature from: {C | F | R | K} Select the Conductivity units from: {ohm-m | ohm-cm | ohm-mm | ohm-ft | ohm-in} Enter the temperatures in column one, the constant coefficient in column two, the coefficient of temperature in column three, and the coefficient of temperature squared in column four. COMMENTS: This portion of the Material Description is a free format text box which may be used to annotate the material. For example, you may want to describe the sources for any property data or techniques used to develop the material or its properties. The minimum requirements for the specific properties of a material which must be provided depend upon the type of analysis you are going to perform. The minimums for six general types of analysis are outlined here. 1. Thermal analysis--Conductivity, Density, and Specific Heat. 2. Fluid (only)--Density and Viscosity. 3. Fluid-Thermal flow analysis--Conductivity, Density, Specific Heat, and Viscosity. 4. Thermal and fluids coupled, with phase change--Conductivity, Density, Liquidus, Solidus, Specific Heat, and Viscosity. 5. Stress--Conductivity, Density, Liquidus, Solidus, Young’s Modulus, Thermal Expansion Coefficient, Poisson’s Ration, Density, and Specific Heat. 6. Induction heating--Magnetic Permeability and Electrical Conductivity.

Remarks

For a material undergoing phase change, there are three ways to PAGE 3 - 62


MATERIALS

account for the latent heat of fusion. 1. Modified specific heat function. This involves converting the latent heat into an equivalent specific heat spike over the freezing range. 2. A continuous enthalpy function can be generated by integrating the specific heat over temperature along with the latent heat. If such a function is specified, it will take precedence over the specific heat. 3. A user specified latent heat value many be used along with a fraction solid curve and the specific heat, and ProCAST will automatically compute an enthalpy curve. The values of the liquidus and solidus temperature are used in a fluids analysis to determine when the material is in the mushy freezing range. A transition is made then to a D’Arcy type flow solution, i.e., porous media flow, rather than a full Navier-Stokes flow. If you are performing a thermal only solution, the liquidus and solidus temperatures have no effect. If you describe a property by entering data as a linear function of temperature table and save the table, the linear function will override any value, for this property, which was specified in the constant window. If you describe a property by entering data as a piecewise quadratic function of temperature table and save the table, the quadratic function will override any value, for this property, which was specified in the constant window or as a linear function. The form of the quadratic function is F = A + BT + CT2. The temperature value for each row indicates the beginning of the range of applicability. There must be at least two rows filled out for the function to be graphed. The temperature from the last row is used as the upper bound for the function. The A, B, and C values of the last row are ignored and can be left blank. When a piecewise quadratic property function with multiple intervals is used in ProCAST, the function is searched from the highest temperature downwards to find the correct temperature interval. Related Topics

DATABASE FACILITY, TABLE MAINTENANCE


MATERIALS

MATERIALS ASSIGN Description

ASSIGN is a push button in the MATERIALS menu. It provides the capability to associate properties from the database with element ID’s in the model.

Method

ASSIGN is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. It also displays a table of the materials in the materials database. The figure shown here illustrates a display for a model with two Material Regions and the Operate Material Database as Rotary Toggle entries. Switches The background of each Region ID#, shown in column one of this table, is displayed in a different color. When you select an entry from this table by clicking on the ID#, the elements in the model with a corresponding ID number will be drawn in the work window pane in the same color as its respective table entry. You may also click in the second column without redrawing the mesh.

PAGE 3 - 64


Toggle Switches Time Step Update Frequency

MATERIALS

To assign a material to a region of the model: 1. Select the region by clicking the left mouse button when the cursor is over the desired table entry. 2. Select a material from the database by moving the cursor down to the window displaying the MATERIAL DATABASE entries. If the material you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired material entry, click on it. 4. ASSIGN the material to the region by clicking the ASSIGN push button. This will place the material name in column two of the Assignment Table. To associate materials with other regions, repeat steps one through four. In addition to associating materials with elements, ASSIGN provides the capability to further define how each material is to be used in the simulation. These definitions are indicated in columns three, four, and five and represent TYPE, MOLD, and UPDATE respectively. TYPE may contain one of four possible values. The entry in column three, titled T, of each row is a rotary toggle switch. Successive clicks on the contents of this column will cycle through the possible choices. Valid material types are: T Thermal, F Fluid, I Filter, and O Foam. When you change this setting, PreCAST checks the database to make sure that you have defined the properties required to satisfy the TYPE designation you have specified. Select the type of material from the following choices: {T | F | I | O}. MOLD may contain Yes or No to indicate that this material is part of the mold. The entry in column four, titled M, of each row is a toggle switch. Successive clicks on the contents of this column will switch between the Y and N values.


MATERIALS

UPDATE may contain a value to indicate the time step frequency for integrating the finite element matrices. By default this is done at every time step. However, if the material properties vary slowly with temperature, as they typically do with molds, you may wish to recompute the matrices much less frequently. This saves a considerable amount of CPU time. Select a row from the Assignment table by clicking the left mouse button when the cursor is over the desired entry. Move the cursor to the Edit Value text input line. Type the numerical value to indicate the desired time step frequency and press ENTER. This will place the entered value in column five, titled U, of the selected row. When you are satisfied with the assignments and their T, M and U settings, click on the QUIT push button in the Material Assignment table or click on a push button in the Main Function Banner. This will store the assignments and close the display. Remarks

The letter shown in column two, before a material name, in the Material Database display indicates that the minimum required properties have been defined for this material to be used in specific types of simulations. The letter F indicates that the material has the minimum required properties for a fluids simulation. The letter T signifies that the minimum requirements for a thermal only analysis are satisfied. An asterisk * shows that there is insufficient data for the material to be used in any type of simulation, except a fluid only simulation. If you are performing a fluid only analysis and this column is marked with an asterisk, you should verify that the Density and Viscosity have been specified for the material. In practice, all non-fluid regions of the model should be specified as the mold. This is particularly true if the simulation is to encompass a number of casting cycles such as in die casting or permanent mold casting. The material IDs which constitute the mold should be indicated with a Y.

PAGE 3 - 66


MATERIALS

You may examine and/or modify the material properties for Material Database entries by clicking the READ/MODIFY push button in the Material Database display window. This will display the Material Description Display as shown here.

Further use of this capability is explained in the MATERIALS DATABASE section of this manual. Related Topics

DATABASE FACILITY, TABLE MAINTENANCE, MATERIALS DATABASE


MATERIALS

MATERIALS STRESS Description

STRESS is a push button in the MATERIALS menu. It provides the capability, through a sub-menu, to access the Stress Model Database and to associate stress model characteristics from the database with element ID’s in the model. Using ProCAST’s DATABASE FACILITY you may create, delete, or modify a stress model or its properties in the database. These stress models may then be used for simulation and analysis.

Method

STRESS is activated by clicking on it. This results in the immediate action to display a sub-menu. As shown here, you may then choose to access the stress model database or proceed to the assign function. PreCAST allows you to Read, Add, Copy, and Delete materials from the Materials Database. These capabilities are described in the DATABASE FACILITY section of this manual. You should also refer to the TABLE MAINTENANCE section of this manual which describes ProCAST’s graphical interface for maintaining tables. This section will discuss the requirements for adding a stress model to the database and how you specify individual properties and attributes for that model. This section will also discuss how you associate elements in your model with the stress database entries using the assign function. You select from the sub-menu by clicking on the desired function. When you click on the DATABASE push button in the submenu, it results in the immediate action to display a table containing any stress models which may be in the database. The figure shown here illustrates a display of the models in the

PAGE 3 - 68


MATERIALS

Stress Database. To add a stress mechanical model to the database, click on the ADD push button in the Stress Database display. This will result in the immediate action to open a blank Stress Description which is shown below. Note that PreCAST has entered the USER name and the DATE for you.

The minimum requirement for adding a stress model to the database is to give it a name and define its properties. The individual properties required depends upon the type of material selected and the modeling and analysis to be done. The syntax and options available for the Stress Definition are discussed below. MATERIAL NAME: Enter the name you want to give the new material. The material name must begin with an alphabetic character and may include upper and lower case characters.


MATERIALS

MATERIAL TYPE: Select the type of material you are adding. ProCAST displays the MATERIAL TYPE as a rotary toggle button. Successive clicks on this push button will cycle through the available choices. The available choices are: LINEAR ELASTIC PLASTIC, LINEAR HARDENING PLASTIC, POWER LAW HARDENING VISCOPLASTIC 1, LINEAR HARDENING VISCOPLASTIC 1, POWER LAW HARDENING VISCOPLASTIC 2, LINEAR HARDENING VISCOPLASTIC 2, POWER LAW HARDENING PROPERTIES: Properties are displayed as a group of check boxes or push buttons. To specify a property, click on the desired property’s check box. Selecting a property in this manner will result in the immediate action to display an additional option menu which will allow you to describe the property as either a CONSTANT or as a LINEAR function. This option menu is shown here. Properties which are not applicable to a specific material type will be shaded dark red. This is illustrated in the figure above, the FLUIDITY, YIELD STRESS, HARDENING PARAM., and VISOPLASTIC FLOW POTENTIAL properties are not applicable for the LINEAR ELASTIC material type. Additionally, ProCAST dynamically displays property names based upon the material type option you have selected. If you select the CONSTANT option, an input box similar to the one shown here will be displayed. It will contain a text input line and may contain a rotary toggle switch for the units of measure. Successive clicks on this push button will toggle through the available options. To enter the desired value for this property or attribute move the cursor to the text input line and type the value. When you click on the APPLY push button, the data entered will be stored, the dialog box will be closed, and the property’s check box on the Stress Definition display will be highlighted in light blue. You may click on the CANCEL push button to close the dialog box without saving the data.

PAGE 3 - 70


MATERIALS

Selecting the LINEAR option will result in the immediate action to display an input table. This table, like the dialog box for a constant, may contain rotary toggle switches for the units of measure. As shown in this example for Elastic Modulus, there are two toggle switches which also serve as the column sub-headings for the table. Select the desired units of measure by clicking on the column heading push buttons. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and press the ENTER key. This will place the value in the table and move the cursor to the next available table entry. When you are satisfied with the table entries, click on the STORE push button, the data in the table will be stored, the dialog box will be closed, and the property’s check box on the Stress Definition display will be highlighted in light blue. You may click on the GRAPH push button to display a graph of the function. You may click on the ERASE push button to erase the entire contents of the table. You may click on the CANCEL push button to close the dialog box without saving the data. The syntax options for Stress Properties will be presented below. For convenience of presentation, all of the properties will be described here. In practice, ProCAST will only display those properties which are valid for each material type.


MATERIALS

ELASTIC MODULUS Constant: Select the units from the following choices: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Elastic Modulus units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the temperatures in column one and Elastic Modulus values in column two. FLUIDITY Constant: Select the units from the following choices: {1/sec | 1/min} Linear function: Select the Temperature from: {C | F | R | K} Select the Fluidity units from: {1/sec | 1/min} Enter the temperatures in column one and Fluidity values in column two. HARDENING EXPONENT Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Hardening Data values in column two. HARDENING PARAMETER Constant: Select the units from the following choices: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Hardening Data units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the temperatures in column one and Hardening Data values in column two.

PAGE 3 - 72


MATERIALS

POISSON’S RATIO Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Poisson’s Ratio values in column two. STRENGTH PARAMETER Constant: Select the units from the following choices: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Yield/Strength units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the temperatures in column one and the Yield/Strength values in column two. THERMAL EXPANSION Constant: Select the units from the following choices: {1/K | 1/C | 1/F | 1/R} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Thermal Coefficient units from: {1/K | 1/C | 1/F | 1/R} Enter the temperatures in column one and Thermal Coefficient values in column two. VISCOPLASTIC FLOW POTENTIAL Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Visco Potential values in column two.


MATERIALS

YIELD STRESS Constant: Select the units from the following choices: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Select the Yield/Strength units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia |Ksi | lb/ft**2} Enter the temperatures in column one and Yield/Strength values in column two. COMMENTS: This portion of the Stress Description is a free format text box which may be used to annotate the material. For example, you may want to describe the sources for any property data or techniques used to develop the stress model or its properties.

PAGE 3 - 74


MATERIALS

ASSIGN is a push button in the STRESS sub-menu. It provides the capability to associate properties from the database with element ID’s in the model. ASSIGN is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. It also displays a table of the materials in the materials database. The figure shown here illustrates a display for a model with two Material Regions and the Material Database entries. The background of each Region ID#, shown in column one of this table, is displayed in a different color. When you select an entry from this table by clicking on the ID#, the elements in the model with a corresponding ID number will be drawn in the work window pane in the same color as its respective table entry.


MATERIALS

To assign a stress model to a region of the model: 1. Select the region by clicking on the desired table entry. 2. Select a stress model from the database by moving the cursor down to the window displaying the MATERIAL DATABASE entries. If the material you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired material entry, click on it. 4. ASSIGN the material to the region by clicking the ASSIGN push button. This will place the material name in column two of the Assignment Table. To associate stress models with other regions, repeat steps one through four. When you are satisfied with the assignments, click on the QUIT push button in the Assignment table. This will store the assignments and close the display. You may close this display without storing any values by clicking the CANCEL push button. Remarks

If no assignment is made for a material, it will be taken as perfectly rigid in the stress analysis. The use of mechanical model data is discussed in the Mathematical Formulations section of this manual. If you describe a property by entering data as a linear function of temperature table and save the table, the linear function will override any value, for this property, which was specified in the constant window. You may examine and/or modify the Stress Model properties for Material Database entries by clicking the READ/MODIFY push button in the Material Database display window. This will display the Material Description Display as shown here.

Related Topics

PAGE 3 - 76


DATABASE FACILITY, TABLE MAINTENANCE, MATERIALS DATABASE

MATERIALS

MATERIALS MICRO Description

MICRO is a push button in the MATERIALS menu. It provides the capability, through a sub-menu, to access the Micro Model Database and to associate micro model characteristics from the database with material ID’s in the model. Using ProCAST’s DATABASE FACILITY you may create, delete, or modify a micro model or its properties in the database. These micro models may then be used for simulation and analysis.

Method

MICRO is activated by clicking on it. This results in the immediate action to display a sub-menu. As shown here, you may then choose to access the micro model database or proceed to the assign function. ProCAST allows you to Read, Add, Copy, and Delete micro models from the database. These capabilities are described in the DATABASE FACILITY section of this manual. You should also refer to the TABLE MAINTENANCE section of this manual which describes ProCAST’s graphical interface for maintaining tables. This section will discuss the requirements for adding a micro model to the database and how you specify individual properties and attributes for that model. This section will also discuss how you associate elements in your model with the micro database entries using the assign function. You select from the sub-menu by clicking on the desired function. When you click on the DATABASE push button in the sub-menu, it results in the immediate action to display a table containing any micro models which may be in the database. The figure shown here illustrates this table display, in this case, there are no models in the Micro USING PRECAST, PAGE 3 - 77

MATERIALS

Database. To add a micro model to the database, click on the ADD push button in the Micro Database display. This will result in the immediate action to open a sub-menu, as shown here, which lists the types of micro models which may be defined. The characteristics, input parameters, and options which are available or required vary from one micro model to another. When you choose from this menu, ProCAST will display the appropriate input form and options in a blank Micro Description which is shown below. For convenience of illustration, the example shown is the result of selecting the EQUIAXED DENDRITE option from the sub-menu.

Input Text Line

Rotary Toggle Switch

Property Check Box

Note that PreCAST has entered the USER name and the DATE for you. PAGE 3 - 78


MATERIALS

PreCAST has also entered, as a default, the KEYWORD which is the same as the file prefix you entered when you started PreCAST. The minimum requirement for adding a micro model to the database is to give it a keyword name and enter values for input parameters. All of the micro model descriptions have two input text lines in common: KEYWORD and COMMENTS. Specific other properties which may be required, depend upon the type of micro model selected and the types of materials to which this model is to be applied. The syntax for the common entries are described below. Following these descriptions, the individual options for each available micro model are discussed. KEYWORD: Enter the name you want to give the micro model database entry. The key word must begin with an alphabetic character. COMMENTS: This portion of the Micro Description is a free format text box which may be used to annotate the material. For example, you may want to describe the sources for any property data or techniques used to develop the micro model or its properties. PROPERTIES: Properties are displayed as a group of check boxes, push buttons, text input lines, or a combination of these. This is illustrated in the figure shown above for the Equiaxed Dendrite model. To enter data in a text input line, place the cursor in the text box, type the desired data, and press ENTER. In some cases, the text input line will be accompanied by a rotary toggle switch. These toggle switches allow you to choose the desired value, usually a unit of measure, from a list of options. As shown in the example above, there are optional units of measure for the GIBBS-THOMPSON COEFFICIENT. Successive clicks on the toggle switch will cycle through the available options for units. To specify a property which is displayed in a check box, click on the desired property’s check box. This will result in the immediate action to display an additional option menu or a input dialog box. Some properties may be specified either as constants or as a linear function. An option menu, similar to the one shown here, will allow you to describe the property as either a CONSTANT or as a function of COOLING RATE, TEMPERATURE, or COMPOSITION. ProCAST dynamically displays the appropriate property names, option boxes, and input text lines based upon the type of micro model option you select.


MATERIALS

If you select the CONSTANT option, an input box similar to the one shown here will be displayed. It will contain a text input line. When a property requires that you specify the units for the property, a rotary toggle switch will be displayed in the input box. Successive clicks on this push button will toggle through the available options. To enter the desired value for this property or attribute move the cursor to the text input line and type the value. When you click on the APPLY push button, the data entered will be stored, the dialog box will be closed, and the property’s check box on the Micro Definition display will be highlighted in light blue. You may click on the CANCEL push button to close the dialog box without saving the data. Selecting the COOLING RATE, TEMPERATURE, or COMPOSITION option will result in the immediate action to display an input table. This table, like the dialog box for a constant, may contain rotary toggle switches for the units of measure. As shown in this example for Transformation Temperature, there are two toggle switches which also serve as the column sub-headings for the table. Select the desired units of measure by clicking on the column heading push buttons. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and press the ENTER key. This will place the value in the table and highlight the next available table entry. When you are satisfied with the table entries, click on the SAVE push button, the data in the table will be stored, the dialog box will be closed, and the property’s check box on the Micro PAGE 3 - 80


MATERIALS

Definition display will be highlighted in light blue. You may click on the GRAPH push button to display a graph of the function. You may click on the ERASE push button to erase the entire contents of the table. You may click on the CANCEL push button to close the dialog box without saving the data. The syntax and options for Micro Model Properties will be presented below. For convenience of presentation, the micro models are presented in alphabetical order.


MATERIALS

CAFE MODEL Editor’s Note: The CAFE capability has not yet been implemented in ProCAST.

AVERAGE UNDERCOOLING Editor’s Note: discussion to be added.

Constant: Enter the constant value to be used in the input line. GROWTH COEFFICIENT 1 and 2 Editor’s Note: discussion to be added.

Constant: Enter the constant value to be used in the input line. MAX NUCLEATION SITES Editor’s Note: discussion to be added.

Constant: Enter the constant value to be used in the input line. STD DEVIATION Editor’s Note: discussion to be added.

Constant: Enter the constant value to be used in the input line.

PAGE 3 - 82


MATERIALS

COUPLED EUTECTIC The Coupled Eutectic Growth Models are divided into two categories: Instantaneous Nucleation and Continuous Nucleation. Selecting the COUPLED EUTECTIC model results in opening another sub-menu which provides you with the option to specify either instantaneous or continuous nucleation. This sub-menu is shown here. You select the desired option by clicking the appropriate push button. These models can be applicable to both regular and irregular eutectics. These models also address the growth of both the stable and metastable eutectic. Either selection will result in displaying the input form shown here. The only difference is that the SUBSTRATE DENSITY is given as a function of temperature instead of cooling rate in the CONTINUOUS NUCLEATION model. In the case of continuous nucleation, nucleation begins at the specified nucleation temperature and continues until the maximum undercooling point in the cooling curve is reached. Once nucleated, the nuclei keep on growing. Beyond the point of maximum undercooling, nucleation ceases and the growth process becomes more dominant and the cooling curve shows recalescence. For instantaneous nucleation, you specify the substrate density as a fraction of cooling rate with the assumption that nucleation occurs at a unique temperature instantaneously.


MATERIALS

CRITICAL COOLING RATE is the rate at which you get the stable-tometastable eutectic transition. For a given melt chemistry, this can be obtained from simple experiments. You should enter the absolute value of the cooling rate. If you are using this model for stable eutectic growth only, then enter a very high value for the critical cooling rate parameter. This will avoid any formation of metastable eutectic. Constant: Select the Cooling Rate units from the following choices: {K/sec | F/sec | C/sec | R/sec | K/min | F/min | C/min | R/min} Enter the constant value to be used in the input line. LAMELLAR SPACING is used for modeling the growth of metastable eutectic. These data must be obtained from experiment. With increasing cooling rate, the lamellar spacing is expected to decrease. Linear function: Select the Cooling Rate units from: {K/sec | F/sec | C/sec | R/sec | K/min | F/min | C/min | R/min} Select the Lamellar spacing units from: {m | cm | mm | ft | in} Enter the cooling rate values in column one and Lamellar spacing values in column two. METASTABLE GROWTH CONSTANT Constant: Select the units from: {m/sec/K**2 | cm/sec/K**2 | mm/sec/K**2 | ft/sec/F**2 | in/sec/F**2 | m/min/K**2 | cm/min/K**2 | mm/min/K**2 | ft/min/F**2 | in/min/F**2} Enter the constant value to be used in the input line. PARTITION COEFFICIENT gives the ratio of solute content in the solid to that in the liquid. Often, this quantity is less than one, signifying that solute will be rejected into the liquid at the solid/liquid interface. When this quantity is greater than one, the region just ahead of the solid/liquid front is depleted of solute (below the base level). This parameter has no unit. This information is needed to calculate the instantaneous stable eutectic temperature as solidification proceeds. During eutectic growth, the solute level will change in the liquid region of a eutectic grain as solidification proceeds. Depending on the amount of solute in the liquid, the eutectic temperature will change. However, the metastable eutectic temperature is assumed to be stationary at this point. The partition coefficient PAGE 3 - 84


MATERIALS

may be entered as a constant or as a function of temperature. The temperature function should be used when the liquidus slope in the binary phase diagram is not constant. Constant: Enter the Partition Coefficient value in the input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Partition Coefficient values in column two. SOLVENT MELTING POINT refers to the melting point of the solvent element or of the pure metal. For example, if your material is a Fe-4.3%C eutectic, you will enter the melting point of pure Fe as the solvent melting point. Here iron is the solvent and carbon is the solute. Constant: Select the Temperature from: {C | F | R | K} Enter the constant value to be used in the input line. STABLE GROWTH CONSTANT is the proportionality constant describing the growth rate of eutectic cells which is proportional to the square of the undercooling ahead of the solid/liquid interface. A typical value for a Fe-Graphite eutectic in cast iron is of the order of 7e-7 cm/sec/K2. This number will vary depending on the material chosen. For a given material, this number may be obtained from the appropriate growth mechanism or from the literature. Constant: Select the units from: {m/sec/K**2 | cm/sec/K**2 | mm/sec/K**2 | ft/sec/F**2 | in/sec/F**2 | m/min/K**2 | cm/min/K**2 | mm/min/K**2 | ft/min/F**2 | in/min/F**2} Enter the constant value to be used in the input line.


MATERIALS

SUBSTRATE DENSITY is used to enter nucleation data. Substrate density can be entered as a function of either the cooling rate or temperature depending upon whether you chose the Instantaneous or the Continuous Nucleation model. Based upon that choice, PreCAST will display the correct input dialog options when you select the SUBSTRATE DENSITY parameter. If you chose Instantaneous, you will specify the substrate density as a function of the cooling rate. If you chose Continuous, you will specify the substrate density as a function of temperature. Allowing the substrate density to vary as a function of cooling rate allows for a non-uniform distribution of grain sizes across a casting. If you expect to have metastable eutectic formation, one of the entries should contain the critical cooling rate with the corresponding value of substrate density for the metastable eutectic. You may need to obtain this data from a carefully conducted experiment. As long as the melt chemistry and process parameters do not change very much, these data can be used for different simulations. For Instantaneous, specify: Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Substrate Density units from: {1/m**3 | 1/cm**3 | 1/mm**3 | 1/ft**3 | 1/in**3} Enter the Cooling Rate values in column one and Substrate Density values in column two. For Continuous, specify: Linear function: Select the Temperature units from : {C | F | R | K} Select the Substrate Density units from: {1/m**3 | 1/cm**3 | 1/mm**3 | 1/ft**3 | 1/in**3} Enter the Temperature values in column one and Substrate Density values in column two.

PAGE 3 - 86


MATERIALS

TRANSFORMATION TEMPERATURE refers to the temperature at which eutectic solidification begins to nucleate in the liquid. This parameter can be a constant or a function of cooling rate. With an increase in cooling rate, the transformation temperature is expected to drop from the equilibrium value. In the case of a stable to metastable transition, the critical cooling rate value you chose needs to be one of the entries in the transformation temperature vs. cooling rate table. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two. DUCTILE IRON EUTECTIC The eutectic growth process in ductile iron is a divorced growth of austenite and graphite, which do not grow concomitantly. This growth is simulated beginning with an instantaneous nucleation model and a growth model that solves the diffusion a carbon from liquid through the austenitic shell into graphite nodule.


MATERIALS

TRANSFORMATION TEMPERATURE refers to the temperature at which eutectic solidification begins. This parameter can be a constant or a function of cooling rate. With an increase in cooling rate, the transformation temperature is expected to drop from the equilibrium value. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two. NODULE COUNT allows you to describe the nucleation data. The nucleation law used is instantaneous in nature, meaning that all the grains are nucleated at the same temperature. You may choose to enter the nucleation data as a function of the cooling rate. Normally, a high value of nodule count is associated with a high value of cooling rate. However, if you wish to use a constant value for the nodule count, you may enter two identical values of the nodule count for a desired range of cooling rates. Be careful about the unit of nodule count. The number required here should be per unit volume. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Nodule Count units from: {1/m**3 | 1/cm**3 | 1/mm**3 | 1/ft**3 | 1/in**3} Enter the Cooling Rate values in column one and Nodule Count values in column two.

PAGE 3 - 88


MATERIALS

DUCTILE IRON EUTECTOID This model is used to simulate the solid state transformation in ductile iron. It may be used during the eutectoid transformation while describing the complete phase transformation of ductile iron from pouring temperature to room temperature. It may also be used when the iron is heated from room temperature to the austenitizing temperature and then annealed or normalized as part of a heat treatment procedure. This model simulates the decomposition of austenite into ferrite and graphite at the stable eutectoid temperature and austenite to pearlite at the metastable eutectoid temperature. These stable and metastable temperatures are known from the literature. Usually this model should be used in conjunction with the eutectic ductile iron model. However, if you are just interested in modeling the solid state transformation starting from a temperature less than the eutectic temperature, then you may use this model alone. TRANSFORMATION TEMPERATURE is used to enter the eutectoid transformation temperature as a constant or as a function of cooling rate. The maximum stable eutectoid temperature used is 1063 (K. Therefore, your transformation temperature should be 1063 (K and greater than the metastable eutectoid temperature, which is taken as 1033 (K. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two.


MATERIALS

NODULE COUNT allows you to describe the nucleation data. The nucleation law used is instantaneous in nature, meaning that all the grains are nucleated at the same temperature. You may choose to enter the nucleation data as a function of the cooling rate. Normally, a high value of nodule count is associated with a high value of cooling rate. However, if you wish to use a constant value for the nodule count, you may enter two identical values of the nodule count for a desired range of cooling rates. Be careful about the unit of nodule count. The number required here should be per unit volume. If you have a eutectic model for the liquid/solid transformation, then the same nodule count values may be entered here. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Nodule Count units from: {1/m**3 | 1/cm**3 | 1/mm**3 | 1/ft**3 | 1/in**3} Enter the Cooling Rate values in column one and Nodule Count values in column two. EQUIAXED DENDRITE This model is based on instantaneous nucleation, whereby the final grain size is known from the nucleation model.

PAGE 3 - 90


MATERIALS

ALLOY COMPOSITION refers to the composition of the solute in solvent in wt% units. For example, if your casting material is a binary Al-7%Si alloy, then you would set the alloy composition to 7 (wt%). For a multi component alloy system, one needs to use an approximate pseudo-binary system and enter the weighted solute content. For example, in case of cast iron the appropriate procedure will be to enter the carbon equivalent value. Constant: Enter the constant value to be used in the input line. DIFFUSIVITY is used to describe the solute diffusivity in liquid. This parameter may be a constant quantity or a function of temperature. Generally, diffusivity is expected to change with temperature as solidification proceeds. Constant: Select the Diffusivity units from the following choices: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature units from: {K | C | F | R} Select the units from: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the temperatures in column one and Diffusivity Data values in column two. GIBBS-THOMPSON coefficient is used for calculating the curvature undercooling at the dendrite tip. A typical value for an Al-Si alloy is 2.0 * 10-7 m*K. This is a material constant. Constant: Select the units from: {m*K | cm*K | mm*K | ft*F | in*F} Enter the constant value to be used in the input line.


MATERIALS

LIQUIDUS SLOPE corresponds to the liquidus slope in a binary or a pseudo-binary phase diagram. Please note that the slope is expected to be a negative quantity and you may have to select the appropriate side of the phase diagram. The liquidus slope can be a constant quantity or a linear function of solute composition. If you select the function of composition, make sure that you enter solute concentration in wt %. Constant: Select the Liquidus Slope units from the following choices: {K/wt% | C/wt% | F/wt% | R/wt%} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Liquidus Slope units from: {K/wt% | C/wt% | F/wt% | R/wt%} Enter the Solute Concentrations in column one and Liquidus Slope data values in column two. PARTITION COEFFICIENT gives the ratio of solute solubility in the solid to the liquid. Often, this quantity is less than one, signifying that solute will be rejected ahead of the dendrite tip. When this quantity is greater than one, the region just ahead of the tip is depleted of solute (below the base level). This parameter has no unit. This parameter may be given as a constant or as a function of temperature. The temperature function should be used when the liquidus slope in the binary phase diagram is not constant. Constant: Enter the Partition Coefficient value in the input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Partition Coefficient Data values in column two.

PAGE 3 - 92


MATERIALS

SUBSTRATE DENSITY is used to enter nucleation data. The nucleation law used is instantaneous. However, substrate density is allowed to vary as a function of cooling rate. This allows for a non-uniform distribution of grain sizes across a casting. You may need to obtain this data from a carefully conducted experiment. As long as the melt chemistry and process parameters do not change very much, these data can be used for different simulations. A continuous nucleation law cannot be used with this model. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Substrate Density units from: {1/m**3 | 1/cm**3 | 1/mm**3 | 1/ft**3 | 1/in**3} Enter the Cooling Rate values in column one and Substrate Density values in column two. TRANSFORMATION TEMPERATURE refers to the temperature at which the equiaxed dendrites begin to nucleate in the liquid. This parameter can be a constant or a function of cooling rate. With an increase in cooling rate, the transformation temperature is expected to drop from the equilibrium value. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two.


MATERIALS

GRAY IRON EUTECTOID The gray iron eutectoid transformation model is used to simulate the solid state transformation in gray iron. Nucleation and growth of ferrite takes place once the temperature drops below the stable eutectoid transformation temperature. If the transformation of austenite is not complete when the metastable eutectoid temperature is reached, then nucleation and growth of pearlite takes place. This model simulates the decomposition of austenite into ferrite and graphite at the stable eutectoid temperature and to pearlite at the metastable eutectoid temperature. This model uses a statistical model for the nucleation law. Also, it uses the values of growth constants of different phases from the literature. TRANSFORMATION TEMPERATURE refers to the temperature at which eutectic solidification begins or the equiaxed dendrites begin to nucleate in the liquid. This parameter can be a constant or a function of cooling rate. With an increase in cooling rate, the transformation temperature is expected to drop from the equilibrium value. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two.

PAGE 3 - 94


MATERIALS

GRAY/WHITE IRON EUTECTIC This model is a special case of coupled eutectic growth model and is applicable to cast iron only. In cast iron, one may obtain both gray and white iron depending on the melt composition and cooling conditions. Given a controlled melt composition, the most important factor that will determine whether a given region will solidify as white or gray is the cooling rate. This model differs from the Coupled Eutectic Growth Models in that the nucleation is described by a statistical nucleation law. The growth constant values for gray and white iron are obtained from the literature. The COUPLED EUTECTIC GROWTH MODEL can also be used for modeling the solidification of eutectic gray/white iron. GRAY TO WHITE TRANSITION COOLING RATE--you are required to enter the critical cooling rate for the gray to white transition. This parameter should be determined from experiment. Constant: Select the units from the following choices: {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Enter the constant value to be used in the input line.


MATERIALS

TRANSFORMATION TEMPERATURE refers to the temperature at which eutectic solidification begins. This parameter can be a constant or a function of cooling rate. With an increase in cooling rate, the transformation temperature is expected to drop from the equilibrium value. Special care are must be taken in the case of a stable to metastable transition. The critical cooling rate value you chose needs to be one of the entries in the transformation temperature vs. cooling rate table. The critical cooling rate value should correspond to the appropriate metastable eutectic temperature. The metastable eutectic temperature is a constant quantity. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two.

PAGE 3 - 96


MATERIALS

PERITECTIC TRANSFORMATION In a peritectic transformation, liquid reacts with an existing solid phase to form a new solid phase. Once the new solid phase is formed, further reaction between the parent phases is limited by the layer of solid formed. Therefore the rate of reaction is controlled by the diffusion of solute through this layer of the transformed product.

ALLOY COMPOSITION refers to the composition of the solute in solvent in wt% units. For a multi component alloy system, one needs to use an approximate pseudo-binary system and enter the weighted solute content. Constant: Enter the constant value to be used in the input line. EUTECTIC COMPOSITION refers to the final composition that the liquid reaches before the end of solidification. Normally, solidification finishes with a terminal eutectic reaction. For example, you would enter 4.3% as the eutectic composition when the material you selected is cast iron. Constant: Enter the constant value to be used in the input line.


MATERIALS

GIBBS-THOMPSON coefficient is used for calculating the curvature undercooling at the dendrite tip. A typical value for an Al-Si alloy is 2.0 * 10-7 mK. Constant: Select the units from: {m*K | cm*K | mm*K | ft*F | in*F} Enter the constant value to be used in the input line. LIQUID DIFFUSIVITY refers to the diffusion coefficient of the solute element in the liquid phase. In the Fe-C system, this is the diffusion coefficient of carbon or carbon equivalent in liquid. Constant: Select the Diffusivity units from the following choices: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature units from: {K | C | F | R} Select the units from: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the temperatures in column one and Diffusivity Data values in column two.

PAGE 3 - 98


MATERIALS

LIQUIDUS SLOPE corresponds to the liquidus line in a binary or a pseudo-binary phase diagram. Please note that the slope is expected to be a negative quantity. The liquidus slope can be a constant quantity or a linear function of solute composition. If you select the function of composition, make sure that you enter solute concentration in wt %.

The figure shown here is a schematic representation of the FeC peritectic region. The liquidus slope refers to the slope of the line AD. The letter P refers to the peritectic point. In this figure, the equilibrium amount of Reacting Fraction of Solid is given as the ration of PD over ED. Constant: Select the Liquidus Slope units from the following choices: {K/wt% | C/wt% | F/wt% | R/wt%} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Liquidus Slope units from: {K/wt% | C/wt% | F/wt% | R/wt%} Enter the Solute Concentrations in column one and Liquidus Slope data values in column two.


MATERIALS

REACTING FRACTION OF SOLID refers to the amount of solid fraction reacting with the liquid phase to produce the new solid phase. In the peritectic reaction, it means the amount of the primary phase that is reacting with liquid. Actually, this number should be obtained with an equiaxed dendrite model for the growth of the delta phase. However, for the time being, you will have to enter here the equilibrium amount of the primary phase. Constant: Enter the constant value to be used in the input line. SOLID FORMING PARTITION COEFFICIENT refers to the partition coefficient of the solute element in the phase being formed and the liquid phase. In the context of the Fe-C system, this parameter refers to the partition coefficient of carbon or carbon equivalent among the gamma and the liquid phase. This coefficient can be constant or functions of temperature. Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Partition Coefficient values in column two. SOLID REACTING DIFFUSIVITY is the diffusion coefficient of the solute element in the reacting solid phase. In the Fe-C system, this is the diffusion coefficient of carbon in the delta phase. This diffusivity parameter may be a constant or a function of temperature. Constant: Select the Diffusivity units from the following choices: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature units from: {K | C | F | R} Select the units from: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the temperatures in column one and Diffusivity Data values in column two.

PAGE 3 - 100


MATERIALS

SOLID REACTING PARTITION COEFFICIENT refers to the partition coefficient of the solute element among the reacting solid phase and the liquid phase. For the Fe-C system, this means the partition coefficient of carbon or carbon equivalent among the delta and the liquid phase. This coefficient can be constant or functions of temperature. Constant: Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Partition Coefficient values in column two. SOLID FORMING DIFFUSIVITY refers to the diffusion coefficient of the solute element in the forming solid phase. In the Fe-C system, this is the diffusion coefficient of carbon in the gamma phase. The diffusivity parameter may be a constant or a function of temperature. Constant: Select the Diffusivity units from the following choices: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Temperature units from: {K | C | F | R} Select the units from: {m**2/sec | cm**2/sec | mm**2/sec | ft**2/sec | in**2/sec | m**2/min | cm**2/min | mm**2/min | ft**2/min | in**2/min} Enter the temperatures in column one and Diffusivity Data values in column two.


MATERIALS

TRANSFORMATION TEMPERATURE refers to the temperature at which peritectic reaction starts. This can be a constant quantity or a function of temperature. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two. SCHEIL The Scheil model makes the assumptions of complete mixing of solute in liquid and no solute diffusion in the solid phase.

ALLOY COMPOSITION refers to the composition of the solute in solvent in wt% units. For a multi component alloy system, one needs to use an approximate pseudo-binary system and enter the weighted solute content. Constant: Enter the constant value to be used in the input line.

PAGE 3 - 102


MATERIALS

FINAL TEMPERATURE usually corresponds to the eutectic temperature or the temperature at which the solidification ends. If the eutectic temperature value is entered here, then evolution of fraction of solid by this model will stop and an eutectic growth model, if chosen, will control the remaining solidification process. Constant: Select the Temperature from: {C | F | R | K} Enter the constant value to be used in the input line. LIQUIDUS SLOPE corresponds to the liquidus line in a binary or a pseudo-binary phase diagram. Please note that the slope is expected to be a negative quantity. The liquidus slope can be a constant quantity or a linear function of solute composition. If you select the function of composition, make sure that you enter solute concentration in wt %. Constant: Select the Liquidus Slope units from the following choices: {K/wt% | C/wt% | F/wt% | R/wt%} Enter the constant value to be used in the Edit Value input line. Linear function: Select the Liquidus Slope units from: {K/wt% | C/wt% | F/wt% | R/wt%} Enter the Solute Concentrations in column one and Liquidus Slope data values in column two. PARTITION COEFFICIENT gives the ratio of solute solubility in the solid to the liquid. Often, this quantity is less than one, signifying that solute will be rejected ahead of the dendrite tip. Constant: Enter the Partition Coefficient value in the input line. Linear function: Select the Temperature from: {C | F | R | K} Enter the temperatures in column one and Partition Coefficient Data values in column two.


MATERIALS

SOLVENT MELTING POINT refers to the melting point of the solvent element or of the pure metal. For example, if your material is a Fe-4.3%C eutectic, you will enter the melting point of pure Fe. Here iron is the solvent and carbon is the solute. Constant: Select the units from the following choices: {K | F | C | R} Enter the constant value to be used in the input line. TRANSFORMATION TEMPERATURE refers to the temperature at which the solidification begins. This parameter can be a constant or a function of cooling rate. Constant: Select the Temperature from: {K | F | C | R} Enter the Transformation Temperature in the Edit Value line. Linear function: Select the Cooling Rate units from : {K/sec | C/sec | F/sec | R/sec | K/min | C/min | F/min | R/min} Select the Transformation Temperature units from: { K | F | C | R} Enter the Cooling Rate values in column one and Transformation Temperature values in column two. SOLID TRANSFORMATIONS This model is only applicable to the Fe-C system and is used for tracking the fraction transformed for the cases of delta to gamma, gamma to ferrite, and gamma to cementite. If the wt% of carbon equivalent is less than or equal to 0.17%, the delta to gamma transformation will be activated in the appropriate temperature range. The value of this carbon equivalent will control whether gamma to ferrite or gamma to cementite will take place during subsequent the proeutectoid transformation.

WT% CARBON EQUIV PAGE 3 - 104


MATERIALS

Constant: Enter the constant value to be used in the input line. ASSIGN is a push button in the MICRO sub-menu. It provides the capability to associate properties from the database with material ID’s in the model. ASSIGN is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. It also displays a table of the material micro models in the database. The figure shown here illustrates a display for a model with two Material Regions and the Micro Database entries. When you select an entry from this table by clicking on the ID# or the Material Name, the elements in the model with a corresponding ID number will be redrawn in the work window pane in a color unique to the respective table entry.


MATERIALS

To assign a micro model to a region of the model: 1. Select the region by clicking the desired table entry. 2. Select a material from the database by moving the cursor down to the window displaying the MICRO DATABASE entries. If the model you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired micro model entry, click on it. 4. ASSIGN the material to the region by clicking the ASSIGN push button. This will place the database entry number in column three of the Assignment Table. To associate micro models with other regions, repeat steps one through four. You may examine and/or modify the properties for Micro Database entries by clicking the READ/MODIFY push button in the Micro Database display window. When you are satisfied with the assignments, click on the QUIT push button in the Assignment Table. This will store the assignments and close the display. You may close this display without storing any assignments by clicking the CANCEL push button. Remarks

The ultimate aim of micromodeling is to predict the microstructure of castings. The mechanical properties of the castings can then be predicted from a knowledge of the microstructure. Micromodels can not accomplish this task alone however. They have to be incorporated into macromodels to achieve this goal. Coupling the macro- and micromodels is accomplished through the source term in the energy equation. The rate of evolution of the fraction of solid is calculated by the micromodels, which controls the release of latent heat. A combination of different micromodels can be chosen in a single simulation run by adding the appropriate MICRO parameters corresponding to individual micromodels. This is done automatically in PreCAST when different micromodels are assigned to the different materials in the model. PreCAST allows you to assign the desired micromodels to the particular material. The rest of this section will discuss specific issues related to individual micro models. For convenience of presentation, these will be presented alphabetically.

PAGE 3 - 106


MATERIALS

COUPLED EUTECTIC--should be selected when the material chosen will solidify at some stage in a eutectic mode. The eutectic could be a stable or metastable. Both the regular and the irregular eutectic solidification are described with this model. The growth of either stable or metastable eutectic may proceed following either an instantaneous or continuous nucleation law. In the case of regular eutectics, growth of both phases of the eutectic structure are non-faceted in nature. For irregular eutectic, the growth process of one of the phases is faceted. Growth of the faceting phase requires considerably higher entropy of fusion. Examples of faceted growth are graphite growth in stable austenite/graphite eutectic and Silicon in Al-Si eutectic. The metastable austenite/ cementite eutectic is an example of non-faceted/non-faceted type eutectic growth. Growth of both the stable and metastable eutectic are addressed here. Growth of the stable eutectic usually proceeds at a higher temperature. For example, the difference between the stable and metastable eutectic temperature in cast iron is about 6 (C. This value may, however, be influenced by the amount of alloying elements present. A higher cooling rate results in the formation of a metastable eutectic. All of the nucleation and growth types of micromodels discussed here assume bulk heterogeneous nucleation at foreign sites which are already present within the melt or intentionally added to the melt by inoculation. So these models are valid for the equiaxed region of castings. The instantaneous nucleation model is modified to take into account the dependance of cooling rate on the number of nucleation sites or substrates. With an increase in cooling rate or undercooling, the number of substrates increases which explains the existence of more grains in faster cooled regions of a casting. In continuous nucleation, the process starts at the nucleation temperature and proceeds until the stage when the minimum in the cooling curve is attained. Regardless of the nucleation process, the models assume that the grains are equiaxed and that they grow freely in liquid as spheres until they impinge on each other. The micromodels use a correction factor for impingement of grains. The growth process stops when all the liquid is consumed.


MATERIALS

DUCTILE IRON EUTECTIC--At the beginning of the liquid/solid transformation, graphite nodules nucleate in the liquid and grow in the liquid to a small extent. The formation of graphite nodules and their limited growth in liquid depletes the melt locally of carbon in the vicinity of the nodules. This facilitates the nucleation of austenite around the nodules, forming a shell. Further growth of these nodules is possible by diffusion of carbon from the melt through the austenite shell to the graphite nodule. ProCAST simulates this growth beginning with an instantaneous nucleation model that determines the final grain size from the local cooling rate at the onset of solidification. Once the austenite shell is formed around each nodule, the diffusion equation for carbon through the austenitic shell is solved. Boundary conditions are known from the phase diagram because thermodynamic equilibrium is maintained locally. Conservation of mass and solute is maintained in each grain. Because of the density variation resulting from the growth of austenite and graphite, the expansion/contraction of the grain is taken into account by allowing the final grain size to vary. Toward the end of solidification, the grains impinge on each other. DUCTILE IRON EUTECTOID--The eutectoid reaction leads to the decomposition of austenite into ferrite and graphite for the case of the stable eutectoid and to pearlite for the metastable eutectoid transformation. Usually, the metastable eutectoid temperature is lower than the stable eutectoid temperature. Slower cooling rates result in more stable eutectoid structure. EQUIAXED DENDRITE--This model should be used to simulate the primary phase solidification of an off-eutectic alloy. GRAY IRON EUTECTOID--The gray iron eutectoid transformation model is based on the approach used for gray iron eutectic and a statistical distribution is assumed. In this statistical approach, nucleation and growth takes place once the temperature drops below the transformation temperature. When nucleation ends at the minimum point of the cooling curve, the existing nuclei continue growing until the transformed fraction becomes 1. The number of nuclei does not change from this point on.

PAGE 3 - 108


MATERIALS

GRAY/WHITE IRON EUTECTIC--This model is a special case of coupled eutectic growth model and is applicable to cast iron only. If a region of a casting solidifies with a cooling rate higher than the critical cooling rate, then it will be white. The reverse is the case for gray iron. The white structure is brittle and in most gray iron castings, it is considered to be deleterious. This model describes nucleation by a continuous distribution function. PERITECTIC TRANSFORMATION--In conventional models, a new solid is assumed to form at the interface between the parent liquid and solid phases in a peritectic transformation when the liquid reacts with an existing solid phase. Once the new solid phase is formed, the rate of reaction is controlled by the diffusion of solute through the shell of the transformed product. Some researchers have suggested that the peritectic transformation may be achieved through a liquid layer between the parent and the product solid phases. This mechanism has been adopted in the present model. More detailed discussion about these properties, models, data, and their use may be found in the Mathematical Formulations Appendix. Related Topics

DATABASE FACILITY, TABLE MAINTENANCE, MATERIALS DATABASE, MATHEMATICAL FORMULATIONS


MATERIALS

MATERIALS INVERSE Description

INVERSE is a push button in the MATERIALS menu which allows you to select the materials in the model for which the thermophysical properties will be calculated using the inverse calculation method. These calculations will be based upon the geometry, initial conditions, boundary conditions, and thermal history.

Method

INVERSE is activated by clicking on it. This results in the immediate action to display a table displaying a list of the materials in the model. The figure shown here illustrates this display. As shown in this figure, there are three columns on the right side of the table. The headings are: Cp–Specific heat per unit mass, K--Thermal conductivity, and L--Latent heat. Beneath these headings are rows of toggle switches. There is one row of switches for each material in the table. You specify the material properties for each material which are to be calculated using the inverse calculation method by toggling the corresponding switch to the Y or yes position. Successive clicks on these switches will toggle between Y and N or no.

Remarks

If you do Materials--Inverse, you cannot concurrently do either the interface or boundary condition determinations using the inverse method.

Related Topics

MATERIALS

PAGE 3 - 110


INTERFACE

INTERFACE Description

INTERFACE is a push button in the Main Function Banner. This function of PreCAST enables you to describe the thermal interfaces between dissimilar material IDs. It also enables you to add, modify and delete interfacial heat transfer coefficient information in the database and assign these specific interface descriptions to elements in the model. When you activate the INTERFACE push button, a menu is opened which will allow you to choose the interface operation you wish to perform. Selections from the menu provide capabilities which will be discussed in this section.

Method

INTERFACE is activated by clicking on it. The initial menu is shown here. When you select a function from this menu, PreCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting information about the interfaces in the database. You may leave the INTERFACE function by clicking another push button in the Main Function Banner.

Remarks

ProCAST provides the capability and flexibility to add, delete, or modify an interface in the interface database. Once Interface data is in the database, you can proceed to the ASSIGN function to associate these interface definitions with specific elements in the model. The major capabilities of the INTERFACE function of PreCAST will be summarized here. Each capability will be described in greater detail in this manual. DATABASE Provides the data management functions for the interface descriptions and their respective properties in your database. DATABASE allows you to add, delete, copy, and modify entries in the interface database. CREATE Provides the capability to create coincident nodes between pairs of adjacent materials.


INTERFACE

ASSIGN Provides the capability to associate interface properties with elements in the model. MULTI-POINTS Provides the capability for you to “glue” together element regions when the nodes do not align. Multi-points can only be used in a thermal solution or in the mold of a fluids analysis. INVERSE Provides the capability to configure the problem to use the inverse calculation method for the determination of interface heat transfer coefficients. ProCAST’s graphical user interface provides a straight forward and simple procedure for working with the various databases used by ProCAST. This database facility is described elsewhere in this manual. You should read about this facility before attempting to modify the interface database. Related Topics

PAGE 3 - 112


DATABASE FACILITY, TABLE MAINTENANCE, INTERFACE-DATABASE, INTERFACE--CREATE, DATABASE--ASSIGN, DATABASE--MULTI-POINTS, DATABASE--INVERSE

INTERFACE

INTERFACE DATABASE Description

DATABASE is a push button in the INTERFACE menu which accesses the Interface Database. Using ProCAST’s DATABASE FACILITY you may create, delete, or modify an interface or its properties in the interface database. These interface descriptions may then be used for simulation and analysis.

Method

DATABASE is activated by clicking on it. This results in the immediate action to display a table containing any interface descriptions which may be in the database. The figure shown here illustrates a display of the materials in the Interface Database. PreCAST allows you to Read, Add, Copy, and Delete interface descriptions from the Interface Database. These capabilities are described in the DATABASE FACILITY section of this manual. You should also refer to the TABLE MAINTENANCE section of this manual which describes ProCAST’s graphical interface for maintaining tables. This section will discuss the requirements for adding an interface description to the database and how you specify individual properties and attributes for that interface. To add an interface description to the database, click on the ADD push button in the Interface Database display. This will result in the immediate action to open a blank Interface Description and an option sub-menu which are shown below. Note that PreCAST has entered the USER name and the DATE for you.


INTERFACE

The minimum requirement for adding an interface description to the database is to give it a KEY or name and define a heat transfer coefficient. The syntax and options available for the Interface Description are discussed below. KEY: Enter the name you want to give the new interface description. Since you are describing a coefficient for an activity between two materials, it may be helpful to enter a key which will be easy for you to remember. For example, you could enter Al, Fe to identify an interface between Aluminum and Iron or My_Al_SpecialOne, My_Sand for an interface between alloys and materials which you have compounded. The key word must begin with an alphabetic character and may include upper and lower case characters.

PAGE 3 - 114


INTERFACE

HEAT TRANSFER COEFFICIENT: PreCAST provides three ways for you to specify the Heat Transfer Coefficient for an interface. It may be a constant quantity or a function of time and/or temperature. As shown in the option sub-menu in the figure above, these options are: CONSTANT, TIME, or TEMPERATURE, respectively. To select a method, click the left mouse button when the cursor is over the corresponding push button. This will result in the immediate action to display an additional dialog box or data input table. Selecting CONSTANT will open an input box as shown here. Notice that it has a rotary toggle switch for the units of measure and a text input line. Select the desired units of measure by clicking on the UNITS push button. Successive clicks on this push button will toggle through the available options. Select the Interface Coefficient units from the following choices: {W/m**2/K | cal/cm**2/C/sec | cal/mm**2/C/sec | Btu/ft**/F/sec | Btu/in**2/F/sec | cal/cm**2/C/min | Btu**2Fmin | Btu/in**2/F/min} To enter the desired constant value to be used, move the cursor to the text input line and type the value. When you click on the APPLY push button, the data entered will be stored, the dialog box will be closed, and the CONSTANT push button on the Interface Description display will be highlighted in light blue. You may click on the CANCEL push button to close the dialog box without saving the data.


INTERFACE

Selecting the TIME or TEMPERATURE option will result in the immediate action to display the appropriate input table. These tables, like the dialog box for a constant, will contain rotary toggle switches for the units of measure. As shown in this example for TIME, there is a toggle switch which also serves as the column sub-heading for the table.

Rotary Toggle Switch

The TIME option allows you to enter the interfacial heat transfer coefficient as a linear function of time. Select the desired units of measure by clicking on the column heading push button. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and press the ENTER key. This will place the value in the table and move the cursor to the next available table entry. Select the time units from the following choices: {sec | min}

PAGE 3 - 116


INTERFACE

When you are satisfied with the table entries, click on the STORE push button, the data in the table will be stored, the dialog box will be closed, and the TIME push button on the Interface Description display will be highlighted in light blue. The TEMPERATURE option allows you to enter the interfacial heat transfer coefficient as a linear function of temperature. The input display shown here will be displayed when you select the TEMPERATURE option.

Select the Temperature units from the following choices: {K | C | F | R} Select the Interface Coefficient units from the following choices: {W/m**2/K | cal/cm**2/C/sec | cal/mm**2/C/sec | Btu/ft**/F/sec | Btu/in**2/F/sec | cal/cm**2/C/min | Btu**2/F/min | Btu/in**2/F/min} Enter the temperatures in column one and Interface Coefficient values in column two. When you are satisfied with the table entries, click on the STORE push button, the data in the table will be stored, the dialog box will be closed, and the TEMPERATURE push button on the Interface Description display will be highlighted in light blue. For either the TIME or TEMPERATURE options, you may click on the GRAPH push button to display a graph of the function. You may click on the ERASE push button to erase the entire contents of the table. You may click on the CANCEL push button to close the dialog box without saving the data.


INTERFACE

COMMENTS: This portion of the Interface Description is a free format text box which may be used to annotate the interface coefficient. For example, you may want to describe the sources for the data entered or techniques used to develop the data. Remarks

Interfacial heat transfer coefficient information depends on the materials involved, the geometry, coating properties and thickness, and on the relative deformation of the part and mold. Normally, this data is acquired by experiment, although some ballpark numbers are available in the literature. You may apply the Interface Transfer Coefficient by using combinations of the CONSTANT, TIME, and TEMPERATURE definitions. You can have the following combinations: 1. CONSTANT, 2. CONSTANT + TIME, 3. TEMPERATURE, 4. TEMPERATURE + TIME, or 5. TIME. If you complete and save a TEMPERATURE linear function table, the constant value will be set to 1.0. If you apply a constant value, even if it is 1.0, the Temperature Table is abandoned.

Related Topics

PAGE 3 - 118



INTERFACE

INTERFACE CREATE Description

CREATE is a push button in the INTERFACE menu which allows you to create interfaces between selected pairs of adjacent materials. Using this capability you may create coincident nodes between these adjacent materials. Once created, these interface elements may then be associated with interface descriptions for use in simulation and analysis.

Method

CREATE is activated by clicking on it. This results in the immediate action to display a table listing the material combinations which share nodes in the geometry is also displayed. The figure shown here illustrates a geometry and a display which contains two pairs of adjacent materials.

Material 1 Interface

Material 2

Material 3

Creating interface nodes is a three step process. 1. Select a material pair for which you want the interface nodes created. When you click on a material pair, the elements with those material ID’s will be drawn in blue and red in the work window pane. The interface will be highlighted in green. The insert to the figure above illustrates these three items in the work window pane. 2. Set the YES--NO toggle switch for the selected pair to YES. Each row in the Adjacent Materials table represents a material pair. In the right-most column of each entry is a YES--NO toggle switch. Successive clicks on this switch will toggle between YES and NO.


INTERFACE

3. Repeat steps One and Two until all of the desired material pairs have been set to YES. It is not necessary to set the switch to YES for every pair shown. However, you must set the switch to YES for those pairs which should have interface nodes before clicking the EXECUTE push button. 4. Click on the EXECUTE push button in the Adjacent Materials display table. EXECUTE will create the new coincident nodes. These nodes will be displayed as red dots in the work window pane. These new nodes are shown in the example below.

Coincident Nodes

Click on the QUIT push button to close the dialog box. Remarks

The EXECUTE function can only be activated once, not separately for each pair. Execute generates an extra set of nodes at the interface and automatically reorganizes the element connectivities. Once the interface nodes have been created, you can not go back and rearrange your interface selections. The only way to change these interface selections is to start over with a new copy of the initial geometry. Filters do not need interfaces between the fluid and filter. If you create such an interface, the fluid will not flow through the filter.

Related Topics

PAGE 3 - 120


TABLE MAINTENANCE

INTERFACE

INTERFACE ASSIGN Description

ASSIGN is a push button in the INTERFACE menu. It provides the capability to associate heat transfer coefficients from the database with element ID’s in the model.

Method

ASSIGN is activated by clicking on it. This results in the immediate action to display a table containing a list of the material pairs between which exist interface nodes. The first column of this list will contain either a C to indicate that the nodes in this pair are Coincident or an N to indicate that they are Noncoincident. A table of the heat transfer coefficients in the Interface Database is also displayed. The figure shown here illustrates a display for a model which contains one pair of materials with interface nodes. As you click on one of the material IDs in the pair, the two materials are drawn in blue and red in the work window pane.


INTERFACE

To assign an interface coefficient: 1. Select an entry from the Material Pairs DB list by clicking on the desired table entry. The selected entry will be highlighted in red. 2. Select an interface from the database by moving the cursor down to the window displaying the INTERFACE DATABASE entries. If the interface you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired interface entry, click on it. 4. ASSIGN the interface to the material pair by clicking the ASSIGN push button. This will place the interface database sequence number in the DB ENTRY column of the MATERIAL PAIRS DB display. In the figure above, notice that the number “5" has been placed in this column because it corresponds to the selected interface database table entry “Clay, Sand.” To associate interface coefficients with other material pairs, repeat steps one through four. ADD is used for creating interfaces between nonaligning meshes. As shown in the figure here, the nodes in Material 7 and Material 6 do not align. Therefore, when you click on the ADD push button, an input dialog box will open. In this dialog box, you specify the two material numbers for which you want to add and assign an interface. The ADD capability is also used to define the interface between a fluid and a filter. DELETE is used to delete any unwanted interfaces. When you are satisfied with the assignments, click on the QUIT push button in the Material Pairs DB table display or click on a push button in the Main Function Banner. This will store the assignments and close the display. Remarks

The order of the material IDs in each row of the Material Pairs display table is significant. If the interface coefficient to be assigned is a function of temperature, PreCAST will use the surface temperature of the first material ID in the row. You may flip the sequence of the material IDs by clicking on the second ID. Doing so changes the position of the material IDs, however it does not change the materials or the interface. In the figure shown above,

PAGE 3 - 122


INTERFACE

clicking on the number “3" would move it to the column which now contains a “2" and the “2" would be moved to the column which now contains the “3.” The column which was clicked last remains highlighted in red. If you delete an interface, the mesh will not be changed. However, there will not be any interface coefficient assigned. If you intended the interface to be non-coincident and it happens to align, you must delete the interface and re-add it to the model. You may examine and/or modify the interface coefficients in the Interface Database entries by clicking the READ/MODIFY push button in the Interface Database display window. This will display the Interface Description Display as shown here. Related Topics

DATABASE FACILITY, TABLE MAINTENANCE, INTERFACE--CREATE


INTERFACE

INTERFACE MULTI-POINTS Description

MULTI-POINTS is a push button in the INTERFACE menu which allows you to describe thermal constraints between element regions when nodes do not align. The temperatures of the nodes on one side of a multi-point interface are forced to be a linear combination of the nodal temperatures on the other side of the interface. Using this capability you specify tolerances which are used in the search for constraining nodes. Once identified, the weighting factors are computed automatically from the geometry by PreCAST. Multi-points can only be used in a thermal solution or in the mold of fluids analysis. This is because pressure gradients are not well behaved across a multi-point interface. MULTI-POINTS is activated by clicking on it. This results in the immediate action to display a table listing the possible combinations of materials between which multi-point constraints could be created.

Method

In the Material Combinations display, “M” and “S” stand for master and slave IDs. The slave nodes will be constrained by the master nodes. Generally, you would want the coarser mesh to be the master side. You may flip the material IDs, thereby changing the designation of the master side, by clicking on the ID you want to be the master side. Doing so changes the position of the material IDs, however it does not change the materials or the interface. In the figure shown above, clicking on the number “1", in row one column two, would move it to the column which now contains a “2" and the “2" would be moved to the column which now contains the “1.” Accordingly, in this example, material “1" would now be designated as the master side.

PAGE 3 - 124


INTERFACE

Creating multi-point interface constraints is a five step process. 1. Identify a material pair for which you want the interface constraint created. If you click on a material ID in the “M”aster column, the elements with those ID’s will be drawn in red in the work window pane. 2. Set the YES--NO toggle switch for the selected pair to YES. Each row in the Material Combinations table represents a material pair. The third column of each entry is a YES--NO toggle switch. Successive clicks on this switch will toggle between YES and NO. 3. Set the PLANE and PERIMETER tolerances to be used in the search for constraining nodes. 4. Repeat steps One through Three until all of the desired material pairs have been set to YES. It is not necessary to set the switch to YES for every pair shown. 5. Click on the EXECUTE push button in the Material Combinations display table. EXECUTE will calculate the weighting factors. The master nodes will be displayed in red and the slave nodes will be displayed in green in the work window pane. To change the PLANE and/or PERIMETER tolerance, select the desired table value by clicking the left mouse button when the cursor is over the tolerance in the table. This will cause the value to be highlighted in red. Move the cursor to the Edit Value line. Type the new tolerance and press ENTER. This will place the new value in the table entry. Click on the QUIT push button to close the dialog box. Remarks

A multi-point interface is not like a thermal break interface because no heat transfer coefficient is involved. You must assign a different material ID to the elements on either side of the interface, even if they will be assigned the same material properties. A multi-point and a coincident node interface cannot be created between the same material ID pair. Therefore, any material ID pairs which were selected for coincident node interfaces will not appear in the Material Combinations table display.


INTERFACE

PLANE and PERIMETER give tolerances which are used in the search for constraining nodes. PLANE is a tolerance normal to the plane of the interface. PERIMETER is the distance outside the edge of an element face that a slave node can be and still be constrained by the nodes in that face. This is illustrated in the figure shown here. “In-the-Plane” Tolerance

Node

“Perimeter” Tolerance Element Face

Node

Related Topics

PAGE 3 - 126


INTERFACE--CREATE, TABLE MAINTENANCE

INTERFACE

Example

As an example of the use of the multi-point constraints, the following two figures are sketches of the finite element mesh above (shown on the right) and below the multi-point constraint interface plane (shown on the left). Top Element Layout

Bottom Element Layout

Y

Y

Metal

X

Mold

X

The mesh has been created such that the metal elements will be contiguous through the intersection. Therefore, no multi-point constraints need be generated for the metal. The mold elements on either side of the plane will have to be linked by multi-point constraints. Normal to the multi-point interface plane there will be a coincident node interface between the metal and the mold. Some care needs to be taken while performing nodal equivalencing so that the metal nodes are combined but the mold nodes are not.


INTERFACE

INTERFACE INVERSE Description

INVERSE is a push button in the INTERFACE menu which allows you to select the interfaces in the model for which the heat transfer coefficients will be calculated using the inverse calculation method.

Method

INVERSE is activated by clicking on it. This results in the immediate action to display a table listing the coincident and non-coincident interfaces. The figure shown here illustrates this display. As shown in this figure, the column on the right side of the table has the heading indicating the heat transfer coefficient--H. Beneath this heading is a toggle switch. There is one switch in each row of the table and corresponds to each set of defined interfaces in the database. You specify the interfaces which are to be calculated using the inverse method by toggling the corresponding switch to the Y or yes position. Successive clicks on these switches will toggle between Y and N or no.

Remarks

Using the inverse method for calculating an interface heat transfer coefficient may be used in conjunction with Boundary Condition-Inverse. However, it can not be used in conjunction with Materials-Inverse. The initial guess for the calculated interface coefficient is taken as the database value that has been assigned.

Related Topics

PAGE 3 - 128


INTERFACE

BOUNDARY CONDITIONS

BOUNDARY Description

BOUNDARY is a push button in the Main Function Banner. This function of PreCAST enables you to describe boundary conditions and their properties in the database. It also enables you to assign boundary conditions to element faces, nodes, and material IDs in the model. When you activate the BOUNDARY CONDITIONS push button, a menu is opened which allows you to work with the various capabilities associated with Boundary Conditions. Selections from the menu provide access to these capabilities and will be discussed in this section.

Method

BOUNDARY is activated by clicking on it. The initial menu is shown here. When you select a function from this menu PreCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting information about the boundary conditions in the database. These may be used in your model and the analysis to be performed. You may leave the BOUNDARY CONDITIONS function by clicking another push button in the Main Function Banner.

Remarks

The major capabilities of the BOUNDARY CONDITIONS function of PreCAST will be summarized here. Each capability will be described in greater detail in this manual. DATABASE Provides the data management functions for the boundary conditions and their respective properties or attributes in your database. DATABASE allows you to add, delete, copy, and modify entries in the boundary condition database. ASSIGN SURFACE Provides the capability to select element faces or nodes, combine them into sets, and assign boundary conditions to each set. ASSIGN VOLUME Provides the capability to assign heat, momentum, mass, or current density to particular material regions.


BOUNDARY CONDITIONS

PERMEABILITY Provides the capability to account for the trapped gas which escapes through the mold. This is intended primarily for sand or shell molds. INVERSE Provides the capability to configure the problem to use the inverse calculation method for the determination of HEAT boundary conditions: film coefficient, heat flux, or emissivity. When you select from the BOUNDARY CONDITIONS menu, additional sub-menus, input displays, and dialog boxes will be displayed depending upon the function you have selected. ProCAST’s graphical user interface provides a straight forward and simple procedure for working with the various databases used by ProCAST. This database facility is described elsewhere in this manual. You should read about this facility before attempting to modify the materials database. Each of the Boundary Condition menu choices will be described in this section. Related Topics

PAGE 3 - 130


DATABASE FACILITY

BOUNDARY CONDITIONS

BOUNDARY DATABASE Description

DATABASE is a push button in the BOUNDARY menu which accesses the Boundary Condition Database. Using ProCAST’s DATABASE FACILITY you may create, delete, or modify a boundary condition or its properties in the boundary conditions database. These boundary condition descriptions may then be used for simulation and analysis.

Method

DATABASE is activated by clicking on it. This results in the immediate action to display a table containing any boundary conditions which may be in the database. The figure shown here illustrates such a display. PreCAST allows you to Read, Add, Copy, and Delete boundary conditions from the Boundary Condition Database. These capabilities are described in the DATABASE FACILITY section of this manual. You should also refer to the TABLE MAINTENANCE section of this manual which describes ProCAST’s graphical interface for maintaining tables. This section will discuss the requirements for adding a boundary condition to the database and how you specify individual properties and attributes for that condition. To add a boundary condition to the database, click on the ADD push button in the Boundary Condition Database display. This will result in the immediate action to open a sub-menu which lists the types of conditions which may be described. This sub-menu is shown below.


BOUNDARY CONDITIONS

The characteristics, properties, and options which are available or required vary from one Boundary Condition to another. When you choose from this menu, ProCAST will display the appropriate input form and options in a blank Boundary Condition Description which is shown below. For convenience of illustration, the example shown is the result of selecting the CURRENT DENSITY option from the sub-menu. PreCAST also displays an option box above the Boundary Condition Description display. The content of the option box depends upon the type of boundary condition you selected. The option box may contain properties or options which are displayed as a group of check boxes, push buttons, text input lines, or a combination of these. In this case, the current density may be designated as a CONSTANT or as a linear function of TIME. Therefore, there are corresponding push buttons in the option box. If the option box includes a text input line, enter data in a text input line by placing the cursor in the text box, typing the desired data, and pressing ENTER. In some cases, the text input line will be accompanied by a rotary toggle switch. These toggle switches allow you to choose the desired value from a list of options. Successive clicks on the toggle switch will cycle through the available options. Note that PreCAST has entered the USER name and the DATE for you. PAGE 3 - 132


BOUNDARY CONDITIONS

PreCAST has also entered, as a default, the KEYWORD which is the same as the file prefix you entered when you started PreCAST. The minimum requirement for adding a boundary condition to the database is to give it a keyword name. All of the boundary condition descriptions have two input text lines in common: KEYWORD and COMMENTS. The syntax for the common entries are described below. Following these descriptions, the individual options for each available boundary condition are discussed. KEYWORD: Enter the name you want to give the boundary condition database entry. The boundary condition keyword must begin with an alphabetic character and may include upper and lower case characters. COMMENTS: This portion of the Boundary Condition Description is a free format text box which may be used to annotate the boundary condition. For example, you may want to describe the sources for any property data or techniques used to develop the boundary condition or its properties. To specify a property which is displayed in a check box, click on the desired property’s check box. This will result in the immediate action to display an additional option menu or a input dialog box. Some properties may be specified either as constants or as a linear function. An option menu, similar to the one shown here, will allow you to select the property as either a CONSTANT or as a function of TIME, PRESSURE, FLOW RATE, or TEMPERATURE. ProCAST dynamically displays the appropriate property names, option boxes, and input text lines based upon the type of boundary condition option you select. If you select the CONSTANT option, an input box similar to the one shown here will be displayed. It will contain a text input line and may contain a rotary toggle switch for the units of measure. Successive clicks on this push button will toggle through the available options. To enter the desired value for this property or attribute move the cursor to the text input line and type the value.


BOUNDARY CONDITIONS

When you click on the APPLY push button or press ENTER, the data entered will be stored, and the dialog box will be closed. You may click on the CANCEL push button to close the dialog box without saving the data. Selecting other options usually results in the immediate action to display an input table. This table, like the dialog box for a constant, may contain rotary toggle switches for the units of measure. As shown in this example for Surface Load, there are two toggle switches which also serve as the column sub-headings for the table. Select the desired units of measure by clicking on the column heading push buttons. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and press the ENTER key. This will place the value in the table and move the cursor to the next available table entry. When you are satisfied with the table entries, click on the STORE push button, the data in the table will be stored, and the dialog box will be closed. You may click on the GRAPH push button to display a graph of the function. You may click on the ERASE push button to erase the entire contents of the table. You may click on the CANCEL push button to close the dialog box without saving the data. The method, syntax, and options for each Boundary Condition will be presented below. For convenience of presentation, they are presented in alphabetical order.

PAGE 3 - 134


BOUNDARY CONDITIONS

CURRENT DENSITY is used to define the current density flowing through an induction coil. You may enter the current density as a constant or as a function of time. The time function modifies the constant value specified. Accordingly, if you use the TIME option, the constant value you provide will be used. The default constant value is 1.0. Negative values of current density will reverse the current flow. For a 2D electromagnetics problem, a positive value of current density is assumed to flow out of the plane of the model towards the viewer. For a 3D problem, a positive value of current density is assumed to flow in the t or last parametric direction of an element. This type of definition, restricts the construction of the induction coils. These coils must be composed of either hex or wedge elements only. Tetrahedron elements can not be used. Negative values of current density will reverse the current flow. Constant: Select the Current Density units from the following: {amps/m**2 | amps/cm**2 | amps/mm**2 | amps/ft**2 | amps/in**2} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the Current Density units from the following: {amps/m**2 | amps/cm**2 | amps/mm**2 | amps/ft**2 | amps/in**2} Enter the time values in column one and current density values in column two.


BOUNDARY CONDITIONS

DISPLACEMENT Is used to define the x, y, z displacement constraints for a stress problem. You may enter the displacement as a constant or as a function of time. The time function modifies the constant value specified. Accordingly, if you use the TIME option, the constant value you provide will be used. The default time value constant is 1.0. The default DISPLACEMENT setting is No Constraint because you may wish to constrain only one direction. Displacement can be constrained in any or all coordinate directions. The units selected will be applied to all constraint coordinate directions. Constant: Select the Displacement units from the following: {m | cm | mm | ft | in} Enter the constant value to be used in each of the appropriate (X:, Y:, and Z:) input lines. Function of time: Select the time units from: {sec | min} Select the Displacement units from the following: {m | cm | mm | ft | in} Enter the time values in column one and displacement values in column two.

PAGE 3 - 136


BOUNDARY CONDITIONS

HEAT Is used to define heat flux boundary conditions applied to element faces. These conditions may be a combination of prescribed heat flux, convection, and radiation. This is known, by some, as the Cauchy condition. When you select either the FLUX or the AMBIENT TEMP check box, you will presented with an additional option menu from which you may choose to enter values for these characteristics as a constant or as a function of time. When you select either the FILM COEFF or the EMISSIVITY check box, you will be presented with an additional option menu from which you may choose to enter values for these characteristics as a constant, a function of time, and/or a function of temperature. AMBIENT TEMP--indicates the temperature of the environment surrounding the model and is used to calculate the convective and/or radiation heat transfer. See Equations C.8.10 and C.8.11 in Appendix C. Constant: Select the Temperature units from the following: {C | F | R | K} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the Temperature units from the following: {C | F | R | K} Enter the time values in column one and temperature values in column two.


BOUNDARY CONDITIONS

EMISSIVITY--indicates the radiation of heat and is used to calculate radiative heat transfer. See Equation C.8.11 in Appendix C. This value should be between 0 and 1. Constant: Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Enter the time values in column one and emissivity values in column two. Function of temperature: Select the Temperature units from the following: {C | F | R | K} Enter the temperature values in column one and emissivity values in column two. FILM COEFFICIENT--indicates the value of heat transfer and is used to calculate convective heat transfer. See Equation C.8.10 in Appendix C. Constant: Select the film units from: {W/m**2/K | cal/cm**2/C/sec | cal/mm**2/C/sec | Btu/ft**2/F/sec | Btu/in**2/F/sec | cal/cm**2/C/min | Btu/ft**2/F/min | Btu/in**2/F/min} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the film coefficient units from: {W/m**2/K | cal/cm**2/C/sec | cal/mm**2/C/sec | Btu/ft**2/F/sec | Btu/in**2/F/sec | cal/cm**2/C/min | Btu/ft**2/F/min | Btu/in**2/F/min} Enter the time values in column one and film coefficient values in column two. Function of temperature: Select the Temperature units from the following: {C | F | R | K} Select the film coefficient units from: {W/m**2/K | cal/cm**2/C/sec | cal/mm**2/C/sec | Btu/ft**2/F/sec | Btu/in**2/F/sec | cal/cm**2/C/min | Btu/ft**2/F/min | Btu/in**2/F/min} Enter the temperature values in column one and film coefficient values in column two.

PAGE 3 - 138


BOUNDARY CONDITIONS

FLUX--indicates heat transfer in or out of the model. See Equation C.8.9 in Appendix C. Constant: Select the flux units from: {W/m**2/sec | cal/cm**2/sec | cal/mm**2/sec | Btu/ft**2/sec | Btu/in**2/sec | cal/cm**2/min | Btu/ft**2/min | Btu/in**2/min} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the flux units from: {W/m**2/sec | cal/cm**2/sec | cal/mm**2/sec | Btu/ft**2/sec | Btu/in**2/sec | cal/cm**2/min | Btu/ft**2/min | Btu/in**2/min} Enter the time values in column one and flux values in column two. VIEW FACTOR--is a toggle switch which cycles between ON and OFF. This switch indicates whether or not the element faces that will be assigned this data set will be participating in the view factor calculations. Note: If VIEW FACTOR is ON, then the emissivity must be given in this set. If VIEW FACTOR is OFF and the emissivity is specified, then the ambient temperature must also be input.


BOUNDARY CONDITIONS

INJECT Is used to define the mass flow rate of a gas injection port to be attached to selected nodes in the void region of a casting model. This data is used with the trapped gas model for free surface flow to develop a gas overpressure for driving the liquid metal. The mass flow rate can be given as a constant, a function of time, or a function of the back pressure that develops from the trapped gas.

Constant: Select the Mass Flow Rate units from: {kg/sec | g/sec | lb/sec | kg/min | g/min | lb/min} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the Mass Flow Rate units from: {kg/sec | g/sec | lb/sec | kg/min | g/min | lb/min} Enter the time values in column one and mass flow rate values in column two. Function of pressure: Select the Pressure units from the following: {atm | psia | Ksi | lb/ft**2 | N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2} Select the Mass Flow Rate units from: {kg/sec | g/sec | lb/sec | kg/min | g/min | lb/min} Enter the pressure values in column one and mass flow rate values in column two.

PAGE 3 - 140


BOUNDARY CONDITIONS

MAGNETIC POTENTIAL Is used to define the prescribed magnetic potential to be applied to selected nodes in the model. This type of boundary condition is used to set the far-field condition for an electromagnetic analysis. Normally, the potential is set to zero all along the outer boundary of a model. Mesh regions should be extended far enough from the induction coils so that the farfield condition is satisfied. You may enter the Magnetic Potential as a constant or as a function of time. Constant: Select the Magnetic Potential units from the following: {weber/m, weber/cm, weber/mm, weber/ft, weber/in} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the Magnetic Potential units from the following: {weber/m, weber/cm, weber/mm, weber/ft, weber/in} Enter the time values in column one and magnetic potential values in column two


BOUNDARY CONDITIONS

MASS SOURCE Is used to define a fluid mass source. Mass sources can be used to create a source of fluid without explicitly modeling that source in finite elements. Mass sources can move around inside the model, allowing things like retractable nozzles to be modeled. To define a Mass Source you provide the source temperature, the flow rate, and the x, y, z coordinate position. The source temperature, flow rate, and coordinate position can be given as a constant or a function of time. TEMPERATURE Constant: Select the Temperature units from: {C | F | R | K} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the Temperature units from: {C | F | R | K} Enter the time values in column one and temperature values in column two. FLOW RATE Constant: Select the Flow Rate from: {kg/sec | g/sec | lb/sec | kg/min | g/min | lb/min} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the Flow Rate units from the following: {kg/sec | g/sec | lb/sec | kg/min | g/min | lb/min} Enter the time values in column one and flow rate values in column two.

PAGE 3 - 142


BOUNDARY CONDITIONS

X, Y, Z Constant: Select the units from: {m | cm | mm | ft | in} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the units from: { m | cm | mm | ft | in} MOMENTUM SOURCE Is used to define a fluid momentum source which will impose a pressure gradient. Momentum sources can be used to create fluid motion without requiring the object responsible for that motion to be explicitly modeled in finite elements. You may enter the momentum source as a constant or as a function of time. Using the X, Y, Z coordinates, you can specify the direction for a momentum source. Direction can be in any or all coordinate directions. The units selected will be applied to all constraint coordinate directions.

Constant: Select the Source Strength units from the following: {N/m**3, dyne/cm**3, lb/ft**3, lb/in**3} Enter the constant value to be used in each of the appropriate (X:, Y:, and Z:) input lines. Function of time: Select the time units from: {sec | min} Select the Source Strength units from the following: {N/m**3, dyne/cm**3, lb/ft**3, lb/in**3} Enter the time values in column one and source strength values in column two.


BOUNDARY CONDITIONS

POINT LOAD is used in stress problems to define the x, y, and z loads at a point. You may enter the point load as a constant or as a function of time.

The components of a force vector are defined using X, Y, Z coordinates. The units selected will be applied to all coordinate directions. Constant: Select the Point Load units from the following: {dyne | Newton | lb} Enter the constant value to be used in each of the appropriate (X:, Y:, and Z:) input lines. Function of time: Select the time units from: {sec | min} Select the Point Load units from the following: {dyne | Newton | lb} Enter the time values in column one and point load values in column two.

PAGE 3 - 144


BOUNDARY CONDITIONS

PRESSURE is used to define the prescribed pressure to be applied to selected nodes.

You may enter the Pressure as a constant or as a function of time. Constant: Select the pressure units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the pressure units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} Enter the time values in column one and pressure values in column two.


BOUNDARY CONDITIONS

SURFACE LOAD is used in stress problems to define the x, y, and z loads at a surface. You may enter the surface load as a constant or as a function of time.

The components of a force vector are defined using X, Y, Z coordinates. The units selected will be applied to all coordinate directions. Constant: Select the Point Load units from the following: {atm, psia, Ksi, lb/ft**2, N/m**2, Pa, KPa, MPa, bar, dyne/cm**2} Enter the constant value to be used in each of the appropriate (X:, Y:, and Z:) input lines. Function of time: Select the time units from: {sec | min} Select the Point Load units from the following: {atm, psia, Ksi, lb/ft**2, N/m**2, Pa, KPa, MPa, bar, dyne/cm**2} Enter the time values in column one and surface load values in column two.

PAGE 3 - 146


BOUNDARY CONDITIONS

SURFACE NUCLEATION Editor’s Note: The Surface Nucleation boundary condition capability has not yet been implemented in ProCAST.

When you select the SURFACE NUCLEATION menu option, the dialog box shown here will be displayed.

Editor’s Note: discussion to be added.


BOUNDARY CONDITIONS

TEMPERATURE is used to define the prescribed nodal temperatures. Mathematically, this is known as a Dirichlet condition.

You may enter the Nodal Temperature as a constant or as a function of time. Constant: Select the temperature units from: {C | F | R | K} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the temperature units from: {C | F | R | K} Enter the time values in column one and temperature values in column two.

PAGE 3 - 148


BOUNDARY CONDITIONS

TURBULENCE Is used to define the turbulence quantities of intensity and characteristic length to be assigned to mass inflow nodes. This boundary condition is used with the --- turbulence model for high Reynolds number flows. When you select either the INTENSITY or the CHARACTERISTIC LENGTH check box, you will be presented with an additional option menu from which you may choose to enter values for these characteristics as a constant or as a function of time. INTENSITY--indicates a fraction of the bulk velocity. It is the size of the current eddy as compared to the main stream. Constant: Enter the constant value to be used in the input line. The default is .1 (10%). Function of time: Select the time units from: {sec | min} Enter the time values in column one and intensity values in column two. CHARACTERISTIC LENGTH--specifies the length, usually, of the opening through which the stream is flowing. The characteristic length is usually the smallest dimension of the channel. Constant: Select the length units from: {m | cm | mm | ft | in} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the length units from: {m | cm | mm | ft | in} Enter the time values in column one and characteristic length values in column two.


BOUNDARY CONDITIONS

VELOCITY Is used to define a prescribed velocity to be applied to selected nodes. Velocity can be used to describe the Filling Rate. If the velocity is specified as zero it can be used to describe a non-slip boundary condition. For a 3D model, you specify the three components of the direction of the velocity by entering values in the U, V, and W input lines. If you leave one of these input lines blank, it does not default to a value of zero. For a 2D model, you specify the U and V components of this direction, the W component, if entered, is ignored. Even though the total magnitude of the velocity may be modified by functions of time and/or pressure, you are required to provide these components to indicate the orientation of the velocity vector. Leaving one or more of the U, V, and W slots blank does not result in a default value of zero. This is because of certain situations that arise when it is necessary to constrain only one component by itself. For an inlet flow particularly, all three components must be given. The TIME and PRESSURE functions allow you to input functions of time and pressure which modify the velocity magnitude. For example, you might want to give a pressure function which sets an inlet velocity to zero if the pressure exceeds a certain value. This situation might occur if you tried to over fill a casting. To calculate an inlet velocity magnitude; take the total volume of the casting and rigging and divide it by the fill time to yield an inlet flow rate. Then divide the inlet flow rate by the inlet area to give the velocity PAGE 3 - 150


BOUNDARY CONDITIONS

magnitude. One subtle point to be aware of is that ProCAST includes in the inlet area total, the areas of any face that has at least one node assigned to the inlet velocity. Selecting the TIME and PRESSURE push buttons will open table displays which will allow you to input these functions. Constant: Select the velocity units from the following: {m/sec | ft/sec | in/sec | m/min | cm/min | ft/min | in/min} Enter the constant value to be used in each of the appropriate (U:, V:, and W:) input lines. Function of time: Select the time units from: {sec | min} Select the velocity units from the following: {m/sec | ft/sec | in/sec | m/min | cm/min | ft/min | in/min} Enter the time values in column one and velocity values in column two. Function of pressure: Select the pressure units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | lb/ft**2} Select the velocity units from the following: {m/sec | ft/sec | in/sec | m/min | cm/min | ft/min | in/min} Enter the pressure values in column one and velocity values in column two. FILL LIMIT is a slider which allows you to specify, as a percent of full, when an inlet flow should be turned off. For example, if the fill limit is set to 99, the inlet velocity will be set to zero magnitude when the casting is 99% full. You may adjust the FILL LIMIT by clicking the left mouse button on either the right or left arrows, by clicking and dragging the slider knob to the desired position, or by clicking the left mouse button when the cursor is positioned over the slider’s track. A FILL LIMIT boundary condition affects the specific inlet to which it is assigned. In the RUN PARAMETERS you may set the LVSURF parameter to turn off all inlets in the model.


BOUNDARY CONDITIONS

VENT Is used to describe a vent which can be attached to selected nodes on the casting side of the mold-metal interface. VENT is used with the trapped gas model for free surface flow during filling transients. The vent diameter, effective length, and surface roughness all have units of length which can be set independently. You click on the EXIT PRESSURE check box to provide the capability to specify the pressure as either a constant or as a function of time.

Select the Diameter, Length, Roughness units from: {m | cm | mm | ft | in} Enter the constant value to be used in each of the appropriate input lines. Constant: Select the Pressure units from: {atm | psia | Ksi | lb/ft**2 | N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2} Function of time: Select the time units from: {sec | min} Select the Pressure units from: {atm | psia | Ksi | lb/ft**2 | N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2} Enter the time values in column one and exit pressure values in column two.

PAGE 3 - 152


BOUNDARY CONDITIONS

VOLUMETRIC HEAT Is used to define a volumetric heat source or sink. A positive value is used to describe a heat source and a negative value to describe a heat sink. You may specify the Volumetric Heat as a constant or as a function of TIME and/or TEMPERATURE. The time function modifies the constant value specified. Accordingly, if you use either of these options, the constant value you provide will be used. The default constant value is 1.0. Constant: Select the Volumetric Heat units from: {W/m**3 | cal/cc/sec | Btu/ft**3/sec | Btu/in**3/sec | cal/cc/min | Btu/ft**3/min | Btu/in**3/min} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Enter the time values in column one and heat modifier values in column two. Function of temperature: Select the Temperature units from: {C | F | R | K} Enter the temperature values in column one and heat modifier values in column two. Remarks

None.

Related Topics



BOUNDARY CONDITIONS

BOUNDARY ASSIGN SURFACE Description

ASSIGN SURFACE is a push button in the BOUNDARY menu. It provides the capability to select element faces or nodes, combine them into sets, and associate properties from the boundary condition database with these sets in the model.

Method

ASSIGN SURFACE is activated by clicking on it. This results in the immediate action to display a table containing a list of any boundary condition node or face sets which have been defined in the model and their Boundary Condition assignment, if any. Some boundary conditions are applied to nodes, others to faces. A Boundary Condition Set may contain nodes or faces but not both. PreCAST selects nodes or faces according to the Boundary Condition type. ASSIGN SURFACE also displays a table of the boundary conditions in the database. These two table displays are separated by a group of tools with which you may select element faces and nodes and create group sets. The figure shown here illustrates a display for a model with several group sets, the Toolbox, and the Boundary Condition Database entries.

PAGE 3 - 154


BOUNDARY CONDITIONS

The background of a table entry, in either table, will be highlighted in red when it is selected. Group sets or element faces will be drawn in red in the work window pane when their respective set entry is selected. If you created boundary condition sets in the mesh generation package, such as PATRAN or IDEAS, these sets would appear in the top table display. To assign a boundary condition to a group set: 1. Select the set by clicking the desired entry in the Assignment Table. 2. Select a boundary condition from the database by moving the cursor down to the window displaying the Boundary Condition Database entries. If the Boundary Condition you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired boundary condition entry, click on it. 4. ASSIGN the boundary condition data to the group by clicking the ASSIGN push button in the Toolbox. This will place the Boundary Condition key word and ID# in column two of the Assignment Table. To associate boundary conditions with other group sets or element faces, repeat steps one through four. PreCAST also provides the capability to create boundary condition sets. The Toolbox contains the tools you use to create these boundary condition sets. Each tool is represented in the Toolbox as a push button, which may be activated by clicking the left mouse when the cursor is over the corresponding tool. Each of these tools will be described here. For convenience of presentation, they will be described in alphabetical order.


BOUNDARY CONDITIONS

ADD--creates a Boundary Condition group set entry in the Assignment Table. When this tool is selected, it opens a menu, as shown here, listing each type of boundary condition. Select the type of boundary condition to be described by clicking on the desired condition. Clicking on a choice from this menu will result in the immediate action to create an entry in the Assignment Table and close the menu. In the figure shown above, item number six, Turbulence, was added to this table because the corresponding choice was made from the menu at the right. It is important to note, that at this point in the process a group set entry has been created in the assignment table. However, nodes or faces have not yet been assigned to this entry and no boundary condition properties have been assigned. Each of these boundary conditions and their respective properties are discussed in the Boundary Conditions Section of this manual. ASSIGN--associates a boundary condition database entry with a specific boundary condition group set. To make an assignment, follow the four step procedure described above. Please note that the type of data that you select from the database must agree with the type of group set.

PAGE 3 - 156


BOUNDARY CONDITIONS

COPY--enables you to copy the contents of one group set to another. This is useful, for example, when you want to apply temperature and velocity conditions to the same nodes. To copy a group set, click on the group set table entry you want to copy and then click on the COPY push button. There are some restrictions on the COPY operation, depending upon the type of sets involved. You may copy from any nodal boundary condition set to any other nodal set or from any element face boundary condition set to any nodal set. However, you may not copy from nodal sets to face sets. DELETE--removes a Boundary Condition group set entry from the Assignment Table. To remove a group set, select the desired entry in the Assignment Table by clicking on it. This will highlight the selected entry in red. Once the desired set entry has been highlighted, click on the DELETE push button. This will remove the entry from the table and remove the association of any nodes which were stored in this entry. DELETE does not remove nodes from the model. DESELECT--provides the capability to untag faces or nodes in a manner similar to the selection process. To deselect faces or nodes, click on the DESELECT push button. Then drag the cursor over the desired nodes or faces while holding the left mouse button down. You may also create a drag box to enclose a portion of the model by depressing and holding the right mouse button while dragging the cursor to form a box around the desired portion of the model. The SURFACE option will also work for deselection. INTERFACE--provides the capability to tag all faces which are on the interface. This is particularly helpful in die casting for selecting inner surfaces. LINK--provides the capability to establish the relationship between two PERIODIC boundary condition node sets. LINK is used after two PERIODIC node sets have been created (using the ADD tool) and after nodes have been assigned to each of these entries. To LINK two PERIODIC node sets, select one of the sets from the Assignment Table by clicking on it. The selected entry will be highlighted with a red background. Next, click on the LINK push button in the toolbox. The push button will be highlighted with a red background. Move the cursor to the Assignment Table and select the companion set. The second table entry will be highlighted with a green background and PreCAST will USING PRECAST, PAGE 3 - 157

BOUNDARY CONDITIONS

display a Rotation and Transformation Input Display. This is illustrated in the figure shown here.

In the input lines, enter the X, Y, and Z coordinates of two points which define an axis of rotation and give the rotation angle in degrees. You can also input a translation vector by entering the coordinates of the translation in the DX, DY, and DZ input lines. Click on the EXECUTE push button in the input display and PreCAST automatically computes a tolerance value based upon the geometry and determines if the nodes of the two sets match up with the specified transformation. REMAINDER--allows you to tag any free faces which are not a part of any other similar boundary condition. SELECT--allows you to tag surfaces for assignment to a boundary condition set. To select faces or nodes, click on the SELECT push button after clicking on the intended boundary condition set in the Assignment Table. To select faces or nodes, drag the cursor over the desired surfaces or node(s) while holding the left mouse button down. You may also create a drag box to enclose a portion of the model by depressing and holding the right mouse button while dragging the cursor. Once a surface has been selected, its edges will be highlighted in red in the work window pane and the STORE push button in the Toolbox will be highlighted with a blue background to indicate that some faces have been selected but not stored. When triangular faces are selected, the centroid is indicated with a red dot. When quadrilateral faces are selected, the diagonals are drawn in red. SELECT ALL--tags all of the external faces or nodes in the problem . PAGE 3 - 158


BOUNDARY CONDITIONS

Once a face or node has been selected, its edges will be highlighted in red in the work window pane and the STORE push button in the Toolbox will be highlighted with a blue background to indicate that some faces have been selected but not stored. Any faces which were previously assigned to a SYMMETRY set will not be tagged by SELECT ALL. Before using SELECT ALL, you should click on the boundary condition set in the Assignment Table where you intend to STORE the selected surfaces or nodes. STORE--places the selected surfaces or nodes into a boundary condition set in the Assignment Table. Once you have tagged all the faces or nodes that you want to be in the set, click on the STORE push button in the Toolbox. This will store the selected information in the table and restore the background color of the STORE push button. SURFACE--provides the capability to select all faces or nodes of a specific surface once you have selected one face on the surface. After selecting one face on a surface, click on the SURFACE push button in the Toolbox. PreCAST will open an input dialog box similar to the one shown here. Move the cursor to the input line and type a tolerance angle. Click on the APPLY push button in the dialog box and PreCAST will select adjacent faces whose angles between normals are less than the tolerance you specified.


BOUNDARY CONDITIONS

Remarks

SYMMETRY face set and PERIODIC Boundary Condition Node Sets do not require assignments from the boundary condition database. Periodic boundary conditions are handled by creating two PERIODIC sets. For a given pair, the nodes of one set must match up closely to the nodes of the other set after undergoing a specified rotation and translation. You may use the view tools, such as rotate, zoom, move, etc., to manipulate the model in the work window pane to make it easier for you to make your selections. You may examine and/or modify the boundary condition properties for Boundary Condition Database entries by clicking the READ/MODIFY push button in the Boundary Condition Database display window. This will display a Boundary Condition Description Display appropriate to the type of boundary condition selected. The BOUNDARY CONDITIONS-DATABASE section of this manual explains the types of boundary conditions and their parameters and attributes.

Related Topics

PAGE 3 - 160


DATABASE FACILITY, TABLE MAINTENANCE, BOUNDARY CONDITIONS--DATABASE

BOUNDARY CONDITIONS

BOUNDARY CONDITION ASSIGN VOLUME Description

ASSIGN VOLUME is a push button in the BOUNDARY CONDITION menu. It provides the capability to associate properties from the boundary condition database with specific material regions in the model.

Method

ASSIGN VOLUME is activated by clicking on it. This results in the immediate action to display a menu which lists the types of boundary conditions which may be assigned. The figure shown here illustrates this option menu. When you select an option from this menu by clicking the desired push button, PreCAST will display an appropriate combination of table displays. The figure shown here, for HEAT, is an example of these displays. The display for each option in the menu will be similar to this one, with the difference being the content in the boundary condition database display table. The top-most table will contain a list of all the material IDs in the model and the material names which have been assigned to them. Any material ID that has no assignment will have an asterisk “*” in the VOL ASSIGN column. When you click on a table entry its background will be highlighted in red and the elements with the corresponding material ID will be drawn in green in the work window pane. The bottom-most table will contain a list of all the Boundary Conditions in the database which correspond to the option you selected. The procedure for associating USING PRECAST, PAGE 3 - 161

BOUNDARY CONDITIONS

boundary conditions with material regions is the same for each of the optional types of boundary conditions shown in this menu. To assign a boundary condition to a material region: 1. Select the Material by clicking the desired entry in the Assignment Table. 2. Select a boundary condition from the database by moving the cursor down to the window displaying the Boundary Condition Database entries. If the Boundary Condition you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired boundary condition entry, click on it. 4. ASSIGN the boundary condition to the material region by clicking the ASSIGN push button in the Assignment Table. This will place the Boundary Condition ID# in column three of the Assignment Table. To associate boundary conditions with other material regions, repeat steps one through four. You can remove any assignment by selecting the desired row in the Assignment Table and clicking the CANCEL push button in that table display. You may click on the QUIT push button at any time to close option menu or the table displays. CURRENT DENSITY--allows you to assign current densities from the boundary condition database to specific material ID numbers. MASS SOURCE--allows you to assign mass sources from the boundary condition database to specific material ID numbers. If a mass source changes its position over time, just choose the material ID that it starts in. It is not necessary to include all the material IDs that it might travel through. MOMENTUM SOURCE--allows you to assign momentum sources from the boundary condition database to specific material ID numbers. SURFACE HEAT--allows you to assign heat functions from the boundary condition database to specific material ID numbers. This applies a Heat Boundary Gondition to the free surface of a fluid. VOLUMETRIC HEAT--allows you to assign volumetric heat functions from the boundary condition database to specific material ID numbers.

PAGE 3 - 162


BOUNDARY CONDITIONS

Remarks

You may use the view tools, such as rotate, zoom, move, etc., to manipulate the model in the work window pane to make it easier for you to make your selections. You may examine and/or modify the boundary condition properties for Boundary Condition Database entries by clicking the READ/MODIFY push button in the Boundary Condition Database display window. This will display a Boundary Condition Description Display appropriate to the type of boundary condition selected. The BOUNDARY CONDITIONS-DATABASE section of this manual explains the types of boundary conditions and their parameters and attributes.

Related Topics

DATABASE FACILITY, TABLE MAINTENANCE, BOUNDARY CONDITIONS--DATABASE


BOUNDARY CONDITIONS

BOUNDARY PERMEABILITY Description

PERMEABILITY is a push button in the BOUNDARY menu. It provides the capability to account for trapped gas which escapes through the mold by assigning permeabilities to specific mold material regions in the model. Permeability is primarily intended for sand or shell molds.

Method

PERMEABILITY is activated by clicking on it. This results in the immediate action to display a table which lists all of the material IDs in the model. When you select a material name from this list, the background for that row is highlighted in red and the elements with that material ID are redrawn in green in the work window pane. This is to aid you in identifying the location of each material ID. To assign a permeability to a material region: 1. Select the Material by clicking the desired entry in the Assignment Table. 2. Move the cursor to the Edit Value input line. 3. Type the desired value and press ENTER. 4. Select the desired units of measure. The right-most column of each entry in this display contains the units of measure. This is a rotary toggle switch. Successive clicks on this switch will cycle you through the available options. You may chose from: {m**2 | cm**2 | mm**2 | ft**2 | in**2} You can remove any assignment by selecting the desired row in the Assignment Table and entering a value of zero in the Edit Value input line. You may click on the QUIT push button at any time to close this display.

Remarks

None.

Related Topics


BOUNDARY PAGE 3 - 164


BOUNDARY CONDITIONS

INVERSE Description

INVERSE is a push button in the BOUNDARY menu which allows you to select the HEAT boundary conditions in the model for which the Film Coefficient, Flux, and Emissivity properties will be calculated using the inverse calculation method. These calculations will be based upon the geometry, initial conditions, boundary conditions, and thermal history.

Method

INVERSE is activated by clicking on it. This results in the immediate action to display a table listing the HEAT boundary conditions in the model. The figure shown here illustrates this display. As shown in this figure, there are three columns on the right side of the table. The headings are: H--Film Coefficient, Q-Flux, and E--Emissivity. Beneath these headings are rows of toggle switches. There is one row of switches for each HEAT boundary condition in the table. You specify the properties for each boundary condition which are to be calculated using the inverse calculation method by toggling the corresponding switch to the Y or yes position. Successive clicks on these switches will toggle between Y and N or no.

Remarks

You may perform an inverse calculation on all H, Q, and E values, as well as for different HEAT boundary conditions at the same time. You may also calculate these boundary conditions using the inverse method in conjunction with Interface--Inverse.

Related Topics

BOUNDARY CONDITIONS


BOUNDARY CONDITIONS

RADIATION Description

RADIATION is a push button in the Main Function Banner. This function of PreCAST enables you to describe radiation data and apply them to enclosures and moving solids. When you activate the RADIATION push button, a menu is opened which allows you to work with the various capabilities associated with RADIATION. Selections from the menu provide access to these capabilities and will be discussed in this section.

Method

RADIATION is activated by clicking on it. The initial menu is shown here. When you select a function from this menu PreCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting radiation information in the database. These may be used in your model and the analysis to be performed. You may leave the RADIATION function by clicking another push button in the Main Function Banner. The major capabilities of the RADIATION function of PreCAST will be summarized here. Each capability will be described in greater detail in this manual. DATABASE Provides the data management functions for radiation information. You may describe attributes for Emissivity, Temperature, and Velocity and how these factors are to be applied in your model. DATABASE allows you to add, delete, copy, and modify entries in the radiation database. ENCLOSURE Provides the capability to select enclosure faces, combine them into sets, and assign emissivity, temperature, and velocity data to each set. SOLID Provides the capability to assign velocities to solid elements.

Remarks

When you select from the RADIATION menu, ProCAST’s graphical user interface provides a straight forward and simple procedure for working with the various databases used by ProCAST. This database facility is described elsewhere in this manual. You should read about this facility before attempting to modify the radiation database. Related Topics

PAGE 3 - 166



BOUNDARY CONDITIONS

RADIATION DATABASE Description

DATABASE is a push button in the RADIATION menu which accesses the Radiation Database. Using ProCAST’s DATABASE FACILITY you may create, delete, or modify radiation information in the database. This radiation information may then be used for simulation and analysis.

Method

DATABASE is activated by clicking the on it. This results in the immediate action to display a table containing any radiation data entries which may be in the database. The figure shown here illustrates such a display. PreCAST allows you to Read, Add, Copy, and Delete radiation information from the Radiation Database. These capabilities are described in the DATABASE FACILITY section of this manual. You should also refer to the TABLE MAINTENANCE section of this manual which describes ProCAST’s graphical interface for maintaining tables. This section will discuss the requirements for adding radiation information to the database and how you specify individual properties and attributes for each entry. To add a radiation entry to the database, click on the ADD push button in the Radiation Database display. This will result in the immediate action to open a sub-menu which lists the radiation attributes which may be described. This sub-menu is shown below. The characteristics, properties, and methods for defining radiation USING PRECAST, PAGE 3 - 167

BOUNDARY CONDITIONS

information may vary from one attribute to another. When you choose from this menu, PreCAST will display the appropriate input form and options as shown below. For convenience of illustration, the example shown is the result of selecting the EMISSIVITY option from the sub-menu. PreCAST also displays an option box above the Radiation Description display. The content of the option box depends upon the radiation attribute you selected. The option box may contain properties or options which are displayed as a group of push buttons, text input lines, or a combination of these. In this case, emissivity may be designated as a CONSTANT or as a linear function of TEMPERATURE. Therefore, there are corresponding push buttons in the option box. If the option box includes a text input line, enter data in a text input line by placing the cursor in the text box, typing the desired data, and pressing ENTER. In some cases, the text input line will be accompanied by a rotary toggle switch. These toggle switches allow you to choose the desired value from a list of options. Successive clicks on the toggle switch will cycle through the available options. Note that PreCAST has entered the USER name and the DATE for you. PreCAST has also entered, as a default, the KEYWORD which is the same as the file prefix you entered when you started PreCAST. The minimum requirement for adding a radiation entry to the database is to give it a keyword name and define its properties. All of the radiation descriptions have two input text lines in common: KEYWORD and COMMENTS. Other properties, which may be defined, depend upon the type of radiation attribute selected. The syntax for the common entries are described below. Following these descriptions, the individual options for each available radiation attribute are discussed. KEYWORD: Enter the name you want to give the radiation database PAGE 3 - 168


BOUNDARY CONDITIONS

entry. The key word must begin with an alphabetic character and may include upper and lower case characters.

COMMENTS: This portion of the Radiation Description is a free format text box which may be used to annotate the radiation attribute. For example, you may want to describe the sources for any property data or techniques used to develop the radiation information or its method of application. When you select the method for describing an attribute PreCAST dynamically displays the appropriate property names, option boxes, and input text lines. If you select the CONSTANT option, an input box similar to the one shown here will be displayed. It will contain a text input line and may contain a rotary toggle switch for the units of measure. Successive clicks on this push button will toggle through the available options. To enter the desired value for this property or attribute move the cursor to the text input line and type the value. When you click on the APPLY push button or press ENTER, the data entered will be stored, and the dialog box will be closed. You may click on the CANCEL push button to close the dialog box without saving the data. Selecting TIME or TEMPERATURE results in the immediate action to display an input table. This table, like the dialog box for a constant, may contain rotary toggle switches for the units of measure. As shown in this example for Emissivity, there are two toggle switches which also serve as the column subheadings for the table. USING PRECAST, PAGE 3 - 169

BOUNDARY CONDITIONS

Select the desired units of measure by clicking on the column heading push buttons. Successive clicks on these push buttons will toggle through the available options. To enter a table value, select the first or next available table entry, move the cursor to the text input line, type the value, and press the ENTER key. This will place the value in the table and move the cursor to the next available table entry. When you are satisfied with the table entries, click on the STORE push button, the data in the table will be stored, and the dialog box will be closed. You may click on the GRAPH push button to display a graph of the function. You may click on the ERASE push button to erase the entire contents of the table. You may click on the CANCEL push button to close the dialog box without saving the data. The syntax and options available for each type of radiation attribute are discussed below. For convenience of presentation, these are presented in alphabetical order.

PAGE 3 - 170


BOUNDARY CONDITIONS

EMISSIVITY Is used to enter an emissivity value as a constant or as a function of temperature. These emissivities will be applied to enclosure faces. Enclosure faces are required to have an emissivity value if they are to participate in a view factor radiation solution. The CONSTANT and TEMPERATURE values are mutually exclusive. If you STORE either one, its respective push button will be highlighted in blue to indicate that data has been entered and saved.

Constant: Enter the constant value to be used in the input line. Function of temperature: Select the temperature units from: {C | F | K | R} Enter the temperature values in column one and emissivity values in column two.


BOUNDARY CONDITIONS

TEMPERATURE Is used to define temperatures which will be assigned to enclosure faces. Enclosure faces are required to have a temperature value if they are to participate in a view factor radiation solution. You may define the temperature as a CONSTANT value or as a linear function of TIME. The CONSTANT and TIME values are mutually exclusive. If you STORE either one, its respective push button will be highlighted in blue to indicate that data has been entered and saved.

Constant: Select the temperature units from: {C | F | R | K} Enter the constant value to be used in the input line. Function of time: Select the time units from: {sec | min} Select the temperature units from: {C | F | R | K} Enter the time values in column one and temperature values in column two.

PAGE 3 - 172


BOUNDARY CONDITIONS

VELOCITY Is used to define the x, y, z direction of a velocity which may be applied to an enclosure or to solid elements in the model. It also allows you to describe the magnitude of this velocity as a function of time. This is used in the radiation model when you have a furnace, baffles, or other parts moving relative to the casting. A single crystal investment casting is an example. You may enter velocity as a constant or as a function of time. The default value for any component is zero. The time function will multiply the magnitude of the velocity vector. Constant: Select the velocity units from the following: {m/sec | ft/sec | in/sec | m/min | cm/min | ft/min | in/min} Enter the constant value to be used in each of the appropriate (X:, Y:, and Z:) input lines. Function of time: Select the time units from: {sec | min} Select the velocity units from the following: {m/sec | ft/sec | in/sec | m/min | cm/min | ft/min | in/min} Enter the time values in column one and velocity values in column two. Remarks

None.

Related Topics



BOUNDARY CONDITIONS

RADIATION ENCLOSURE Description

ENCLOSURE is a push button in the RADIATION menu. It provides the capability to select enclosure faces, combine them into sets, and assign emissivity, temperature, and velocity data to each set in the model.

Method

ENCLOSURE is activated by clicking on it. This results in the immediate action to display a table containing a list of any enclosure element sets which have been defined in the model and the emissivity, temperature, and/or velocity attributes which have been assigned, if any. A table of the radiation attributes in the database is also displayed. These two table displays are separated by a group of tools with which you may select enclosure faces and create element sets. The figure shown here illustrates these two table displays and the Toolbox. The background of a table entry, in either table, will be highlighted in red when it is selected. Element sets will be drawn in red in the work window pane when their respective set entry is selected.

PAGE 3 - 174


BOUNDARY CONDITIONS

To assign a radiation attribute to an element set: 1. Select the set by clicking on the desired entry in the Assignment Table. 2. Select a radiation attribute from the database by moving the cursor down to the window displaying the Radiation Database entries. If the Radiation entry you want is not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired radiation attribute entry, click on it. 4. ASSIGN the attribute to the element set by clicking the ASSIGN push button in the Toolbox. This will place the radiation attribute ID# in the appropriate column (E, T, or V) of the Assignment Table. To associate radiation attributes with element sets, repeat steps one through four. PreCAST also provides the capability to create enclosure face element sets. The Toolbox contains the tools you use to create these sets. Each tool is represented in the Toolbox as a push button which may be activated by clicking the left mouse button. Each of these tools will be described here. For convenience of presentation, they will be described in alphabetical order. ADD--creates an enclosure face element set entry in the Assignment Table. When this tool is selected, an empty row is added to the Assignment Table. An asterisk “*” will be placed in each column (E, T, V) to indicate that no data has been assigned to that entry. It is important to note that at this point in the process the element set entry has been created in the assignment table. However, elements have not yet been assigned to this entry and no radiation attributes have been assigned. Each of these radiation attributes and their respective properties are discussed in the Radiation Section of this manual. ASSIGN--associates a radiation database entry with a specific enclosure element set. To make an assignment, follow the four step procedure described above. CANCEL--allows you to close the ENCLOSURE displays.


BOUNDARY CONDITIONS

DELETE--removes all enclosure elements from the set an enclosure face element set entry from the Assignment Table. To remove an element set, select the desired entry in the Assignment Table by clicking on it. This will highlight the selected entry in red. Once the desired set entry has been highlighted, click on the DELETE push button. This will remove the entry from the table and disassociate any elements which were stored in this entry. DELETE does not remove elements or nodes from the model. To complete the deletion you must click on the STORE push button. DESELECT--provides the capability to untag faces in a manner similar to the selection process. To deselect faces click on the DESELECT push button. Then drag the cursor over the desired face(s) while holding the left mouse button down. You may also create a drag box to enclose a portion of the model by depressing and holding the right mouse button while dragging the cursor to form a box around the desired portion of the model. SELECT--allows you to tag faces for assignment to an enclosure element set. To select faces click on the SELECT push button after clicking on the intended element set in the Assignment Table. To select faces, drag the cursor over the desired surfaces while holding the left mouse button down. You may also create a drag box to enclose a portion of the model by depressing and holding the right mouse button while dragging the cursor to form a box. Once a surface has been selected, its edges will be highlighted in red in the work window pane and the STORE push button in the Toolbox will be highlighted with a blue background to indicate that some faces have been selected but not stored. Once you release the mouse button, you need to click on SELECT again if you wish to choose more faces. SELECT ALL--tags all of the free enclosure faces in the problem . Once a face has been selected, its edges will be highlighted in red in the work window pane and the STORE push button in the Toolbox will be highlighted with a blue background to indicate that some faces have been selected but not stored. Before using SELECT ALL, you should click on the enclosure set in the Assignment Table where you intend to STORE the selected surface elements.

PAGE 3 - 176


BOUNDARY CONDITIONS

STORE--places the selected surfaces into an enclosure element set in the Assignment Table. Once you have tagged all the faces that you want to be in the set, click on the STORE push button in the Toolbox. This will store the selected information in the table and restore the background color of the STORE push button. Remarks

At a minimum, you must assign emissivity and temperature data to each element set. If the faces in the set are moving relative to the casting, then you need to assign a velocity as well. You may use the view tools, such as rotate, zoom, move, etc., to manipulate the model in the work window pane to make it easier for you to make your selections. You may examine and/or modify the entries in the Radiation Database by clicking the READ/MODIFY push button in the Radiation Database display window. This will display a Radiation Description Display appropriate to the type of radiation attribute selected. The RADIATION-DATABASE section of this manual explains the types of radiation attributes and their parameters. You should also assign ALL enclosure elements to a set or you will receive warning messages from DataCAST.

Related Topics

DATABASE FACILITY, TABLE MAINTENANCE, RADIATION-DATABASE


BOUNDARY CONDITIONS

RADIATION SOLID Description

SOLID is a push button in the RADIATION menu. It provides the capability to assign velocities to solid elements in the model.

Method

SOLID is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. It also displays a table of the velocities in the Radiation Database. The figure shown here illustrates a display for a model with three material regions. When you select an entry from this table by clicking on the ID#, the elements in the model with a corresponding ID number will be drawn in the work window pane in green. To assign a velocity to a region of the model: 1. Select the region by clicking on the desired table entry. 2. Select a velocity from the database by moving the cursor down to the window displaying the RADIATION DATABASE entries. If the velocity you want is

PAGE 3 - 178


BOUNDARY CONDITIONS

not visible in the table at first, you may scroll to the desired entry. 3. When you have located the desired velocity entry, click on it. 4. ASSIGN the velocity to the region by clicking the ASSIGN push button. This will place the velocity’s database sequence number in the “VELOCITY” column of the Assignment Table. To associate velocities with other regions, repeat steps one through four. When you are satisfied with the assignments, click on the QUIT push button in the Velocity Assignment table or select any push button in the Main Function Banner. This will store the assignments and close the display. Remarks

Assigning velocities to solid elements in the model may be used, for example, for baffles which are moving relative to a casting, where you want to solve for the temperatures in the baffles rather than impose them. You may also construct an entire furnace out of solid elements rather than use enclosure elements. Emissivities for the solid elements would be applied as a heat BOUNDARY CONDITION. If you have two groups of solid elements which are moving relative to one another, it is best to apply the velocity to the group with the least number of elements. This minimizes the size of some output files. You may examine and/or modify the properties for Radiation Database entries by clicking the READ/MODIFY push button in the Radiation Database display window. This will display the Radiation Description for the selected table entry. Further use of this capability is explained in the RADIATION DATABASE section of this manual.

Related Topics

DATABASE FACILITY, TABLE MAINTENANCE, RADIATION-DATABASE


INITIAL CONDITIONS

INITIAL CONDITIONS Description

INITIAL COND is a push button in the Main Function Banner. This function of PreCAST enables you to assign initial temperatures to each material ID in the model or extract the initial temperatures from a previous run of ProCAST. Additionally, the FREE SURFACE option in the INITIAL CONDITIONS menu allows you to indicate which volumes in the mesh are initially empty in free surface fluid problems. When you activate the INITIAL CONDITIONS push button, a menu is opened which allows you to work with the various capabilities associated with INITIAL CONDITIONS. Selections from the menu provide access to these capabilities and will be discussed in this section.

Method

INITIAL CONDITIONS is activated by clicking on it. It displays the menu shown here. When you select a function from this menu PreCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting radiation information in the database. These may be used in your model and the analysis to be performed. You may leave the INITIAL CONDITIONS function by clicking another push button in the Main Function Banner. The major capabilities of the INITIAL CONDITIONS function of PreCAST will be summarized here. Each capability will be described in greater detail in this manual. CONSTANT Provides the capability to specify an initial temperature for each material ID in the model.

Remarks

EXTRACT Provides the capability to pull nodal temperatures for a set of materials IDs at a given time step from a previous results file. This is particularly useful in die casting or permanent mold simulations when you want to determine the temperature in the mold after several cycles. Extracted temperatures override initial temperatures.

PAGE 3 - 180


INITIAL CONDITIONS

FREE SURFACE Provides the capability to specify the material volumes which are initially empty. This is only necessary if you are setting up a free surface fluid flow problem. When you select from the INITIAL CONDITIONS menu, ProCAST’s graphical user interface provides a straight forward and simple procedure for working with the parameters and attributes associated with the initial temperature conditions in the model.

Related Topics



INITIAL CONDITIONS

INITIAL CONDITIONS CONSTANT Description

CONSTANT is a push button in the INITIAL CONDITIONS menu. It provides the capability to assign temperatures to material regions in the model.

Method

CONSTANT is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. It also displays an Edit Value input line. The figure shown here illustrates a display for a model with three material regions. When you select an entry from this table by clicking on the ID#, the background of that row is highlighted in red and the elements in the model with a corresponding ID number will be drawn in green in the work window pane. To assign an initial constant temperature to a region of the model: 1. Select the region by clicking on the desired table entry. 2. Enter the temperature by moving the cursor to the Edit Value input line. Type the desired value and press ENTER. 3. Select the temperature units by clicking on the UNITS toggle switch. This is a rotary toggle, successive clicks on it will cycle you through the available options. These options are {C | F | R | K}. To assign temperatures to other regions, repeat steps one through three. You close the display and move to another function of PreCAST or to another function of INITIAL CONDITIONS by clicking the appropriate Main Function Banner or Menu push button respectively.

Remarks

You must specify the initial conditions in the mold.

Related Topics


INITIAL CONDITIONS PAGE 3 - 182


INITIAL CONDITIONS

EXTRACT Description

EXTRACT is a push button in the INITIAL CONDITIONS menu. It provides the capability to assign nodal temperatures to material regions in the model by loading them from a previous simulation results file at the specific time step you designate.

Method

EXTRACT is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. It also displays an Extract Parameters Input dialog box. The figure shown here illustrates a display for a model with three material regions. When you select an entry from this table by clicking on the ID#, the background of that row is highlighted in red and the elements in the model with a corresponding ID number will be drawn in green in the work window pane. In this table, any material which has already been assigned an initial value will be highlighted with a blue background. To extract initial temperatures for a region of the model: 1. Select the region by clicking on the desired table entry. 2. Enter the full path name of the directory where the results file can be found by moving the cursor to the Enter Directory name input line. Type the desired value and press ENTER. If the results are in the current directory, you may enter a period and press ENTER. 3. Enter the prefix that was used for the results file you want to use by moving the cursor to the Prefix input line. Type the desired value and press ENTER. PreCAST will append t.unf to the prefix


INITIAL CONDITIONS

to make a complete file name. 4. Enter the time step number that you want to use as the source of the temperatures for this model by moving the cursor to the Enter Step value input line. Type the desired value and press ENTER. Note: There must be results in the file for the time step you specify. For example, if TFREQ = 5 in the solution file you indicated, the time step you enter must be some multiple of 5. 5. When you are satisfied with the Path, Prefix, Step value entries, click on the APPLY push button in the Extract Parameters Input dialog box. This will place the prefix and step number in the appropriate columns in the list of the materials. To extract temperatures for other regions, repeat steps one through five. Once you have applied the Path, Prefix, and Step value entries, as discussed in step 5 above, you may look at the values in the results file by clicking the DISPLAY push button in the Extract Parameters Input dialog box. You close the display and move to another function of PreCAST or to another function of INITIAL CONDITIONS by clicking the appropriate Main Function Banner or Menu push button respectively. Remarks

EXTRACT is particularly useful in die casting or permanent mold simulations when you want to determine the temperature in the mold after several cycles.

Related Topics

INITIAL CONDITIONS--CONSTANT

PAGE 3 - 184


RUN PARAMETERS

INITIAL CONDITIONS FREE SURFACE Description

FREE SURFACE is a push button in the INITIAL CONDITIONS menu. It provides the capability to specify material regions in the model which are initially empty.

Method

FREE SURFACE is activated by clicking on it. This results in the immediate action to display a table containing a list of the material regions which have been defined in the model. The figure shown here illustrates a display for a model with three material regions. When you select an entry from this table by clicking on the ID#, the background of that row is highlighted in red and the elements in the model with a corresponding ID number will be drawn in green in the work window pane. Material regions in this table which are specified to be initially empty will display the word YES in the EMPTY column of this table. To specify that a material region is initially empty, toggle the EMPTY switch in that row to the desired YES or NO position. Repeat these two steps for each region of the model which is initially empty. You close the display and move to another function of PreCAST or to another function of INITIAL CONDITIONS by clicking the appropriate Main Function Banner or Menu push button respectively.

Remarks

FREE SURFACE is only necessary when you are setting up a free surface fluid flow problem. For flow through a filter, you should specify that the filter is initially empty.

Related Topics

RUN PARAMETERS USING PRECAST, PAGE 3 - 185

RUN PARAMETERS

Description

RUN PARAMETERS is a push button in the Main Function Banner. This function of PreCAST enables you to specify run parameters for the various types of analyses to be performed. Selections from the menu provide access to the available sets of run parameters in ProCAST. This section will discuss these capabilities and how to use them.

Method

RUN PARAMETERS is activated by clicking on it. It displays the menu shown here. When you select a function from this menu PreCAST will display additional Dialog Boxes. These graphical interface tools will guide you through the process of specifying or changing individual run parameters. You may leave the RUN PARAMETERS function by clicking another push button in the Main Function Banner.

Remarks

The RUN PARAMETERS function of PreCAST provides the capability to specify which ProCAST capabilities will be used during the simulation, how they will be used, and other general parameters which will govern the simulation. The names of most frequently changed parameters will be displayed in black. The names of the more advanced or infrequently changed parameters will be displayed in red. Next to selected parameters is a rotary toggle switch which will display the available units for that specific parameter. Successive clicks on these toggle switches will cycle through the available options. To enter or change a value for a parameter, place the cursor in the desired parameter input box, type the value, and press ENTER.

PAGE 3 - 186


RUN PARAMETERS

Information about each parameter is available on-line. To obtain information about a parameter, place the cursor in the desired parameter input box and click on the HELP push button. HELP will display an information window. You close the information window by clicking the QUIT push button in the HELP window. For a specific job, as indicated by the file prefix, PreCAST displays the default values for the run parameters, in the dialog box, until you make a change for that job. If you change a parameter and subsequently RESTART the job, PreCAST will read the prefixp.dat file and use the parameter values which have been saved there as the defaults. Related Topics



RUN PARAMETERS

RUN PARAMETERS UNITS Description

UNITS is a push button in the RUN PARAMETERS menu. It provides the capability to specify the default units of measure to be used in the output files.

Method

UNITS is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the unit of measure types. Next to each category of units is a rotary toggle switch which will display the available options for each of the categories. Successive clicks on these toggle switches will cycle through the available options. The figure shown here illustrates the UNITS dialog box. The UNITS parameters and the available options for each parameter will be presented here. For convenience in presentation, they will be presented in alphabetical order. PUNITS--specifies the pressure units to be used in the outputs. Choose from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} QUNITS--specifies the heat flux units to be used in the outputs. Choose from: { W/m**2 | cal/cm**2/sec | cal/mm**2/sec | Btu/ft**2/sec | Btu/in**2/sec | cal/cm**2/min | cal/mm**2/min | Btu/ft**2/min | Btu/in**2/min} TCUNITS--specifies the thermocouple units to be used in the outputs and is only used for inverse modeling. Choose from: {C | F | R | K} TUNITS--specifies the temperature units to be used in the outputs. Choose from: {C | F | R | K} VUNITS--specifies the velocity units to be used in the outputs. Choose from: {m/sec | cm/sec | mm/sec | ft/sec | in /sec | m/min | cm/min | mm/min | ft/min | in/min} You may close this display and move to another function of PreCAST or to another function of RUN PARAMETERS by clicking the appropriate Main Function Banner or Menu push button respectively.

Remarks

None.

Related Topics

PAGE 3 - 188


RUN PARAMETERS

RUN PARAMETERS GENERAL Description

GENERAL is a push button in the RUN PARAMETERS menu. It provides the capability to control the time stepping algorithm and the type of output to be produced during the simulation.

Method

GENERAL is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the general parameters and, if applicable, units associated with a parameter.

The figure shown above illustrates the GENERAL dialog box. Just below the GENERAL dialog box is a COMMENTS input line. This box allows you to enter your own comments about this job. The comments you enter will be stored in the prefixp.out file. To enter comments, place the cursor in the input line, type your comments, and press ENTER. The GENERAL parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order.


RUN PARAMETERS

AVEPROP--specifies the method to be used in calculating the properties for each element. ProCAST will calculate the properties at each Gauss point or you may specify that the properties be calculated only at the element center and that this value will be used as an average for the whole element. This averaging reduces, somewhat, the finite element integration time required. This averaging does not apply to the specific heat or enthalpy calculations. Choose from: {0 to calculate at each point, or 1 to use the average} The default is 0. CGSQ--specifies the Conjugate Gradient Squared solver flag. The values specified in this parameter may be added together. This allows you to “build” a customized solver approach for your simulation. Choose from: {0 = Use the default iterative solver ( TDMA ), 1 = Use the CGSQ solver on the U momentum equation, 2 = Use the CGSQ solver on the V momentum equation, 4 = Use the CGSQ solver on the W momentum equation, 16 = Use the CGSQ solver on the energy equation, 64 = Use the CGSQ solver on the turbulence intensity equation, 128 = Use the CGSQ solver on the turbulence dissipation equation, or 512 = Use the CGSQ solver on the density equation for compressible flow} The default is 0. CONVTOL--specifies the convergence tolerance which will be used in conjunction with the default non-symmetric iterative solver. Enter a floating (real) value. The default is 1.0000e-04.

PAGE 3 - 190


RUN PARAMETERS

DIAG--specifies the diagonal preconditioning flag for the symmetric solver. Choose from: {0 = use partial Cholesky preconditioning for everything, 8 = use diagonal preconditioning for pressure, 16 = use diagonal preconditioning for energy, and 16384 = use diagonal preconditioning for radiosity} The default is 16384. DT--specifies the initial time step size. Setting DT to zero when INILEV > 0 will cause ProCAST to use the DT at step INILEV. Enter a floating (real) value. The default is 1.0000e-03. Select the units of time from: {sec | min} DTMAX--specifies the maximum time step size. Enter a floating (real) value. The default is 5.0000e+00. Select the units of time from: {sec | min} INILEV--specifies the initial time level. When an analysis is first started, INILEV should be equal to zero. When you are resuming an analysis, INILEV should be set to the time step from which you would like to continue. Note: You must have results for that time step. Enter an integer value. The default is 0. LUFAC--specifies the preconditioning parameter for the CGSQ solver. This parameter may speed-up a “large” model(500,000+ elements, 100,000+ nodes) solution Choose from: {0 to use diagonal preconditioning, or 1 to use partial LU factorization preconditioning} The default is 1. NCYCLE--specifies the number of casting cycles to be simulated in a continuous mode. This parameter is used along with TCYCLE. Both NCYCLE and TCYCLE must be set. This parameter is typically used in die casting, permanent mold problems. Enter an integer value. The default is 0.


RUN PARAMETERS

NEWTONR--turns on the NEWTON Raphson technique for the energy equation. Choose from: {0 to turn off the Newton Raphson technique, 1 to turn the Newton Raphson technique on, or 2 to turn on the Newton Raphson technique and use bsplines} The default is 0. Option 2 results in using b-splines instead of linear line segments in the representation of the thermal properties. It is suggested that all thermal input data be smoothed before attempting to use b-splines. Enter an integer value. The default is 0. NPRFR--specifies the printout frequency. This controls the time step interval at which results are output to the prefixp.out file. Enter an integer value. The default is 1. NRSTAR--specifies the number of allowable restarts before the entire run is abandoned. A restart occurs when the maximum number of corrections is reached. If too many restarts are taking place, it could indicate problems with the model setup. Enter an integer value. The default is 5. NSTEP--specifies the number of time steps to take in the current run and is used in conjunction with TFINAL. ProCAST will terminate the run when it reaches this limit or the TFINAL value, whichever occurs first. Enter an integer value. The default is 100.

PAGE 3 - 192


RUN PARAMETERS

PRNLEV--specifies the level of nodal results to be printed out. The values specified in this parameter may be added together. This allows you to collect combinations of nodal information in a single run. Choose from: {0 = no printout, 1 = nodal velocities, 8 = nodal pressures, 16 = nodal temperatures, 64 = nodal turbulence intensities, 128 = nodal turbulence dissipation rates, 1024 = nodal displacements, 8192 = surface heat fluxes, and 32768 = nodal magnetic potentials} The default is 0. SDEBUG--specifies the level of solution debugging messages to be captured. These messages are written to the p.out file. Choose from: {0 to capture no solution debugging messages, or 1 to obtain information concerning, solver performance, time step control, and the free surface model} The default is 1. TCYCLE--specifies the time of casting cycle to be simulated in a continuous mode. This parameter is used along with NCYCLE. Both NCYCLE and TCYCLE must be set. Enter a floating (real) value. The default is 0.0000e+00. Select the units of time from: {sec | min} TFINAL--specifies the simulated time at which to terminate a ProCAST analysis. If this parameter is zero, the run will be stopped by the NSTEP parameter. If both the NSTEP and TFINAL parameters are set, the simulation will be terminated based upon which parameter is reached first. Enter a floating (real) value. The default is 0.0000e+00. Select the units of time from: {sec | min} TMODR--specifies the time step modification factor for restarts. If MAXCOR correction steps are taken without convergence, the time step is multiplied by TMODR. Therefore, this number should be less than 1. Enter a floating (real) value. The default is 5.0000e-01.


RUN PARAMETERS

TMODS--specifies the time step modification factor for normal stepping. If the number of correction steps is less than or equal to NCORL, the subsequent time step is multiplied by TMODS. If the number of correction steps is greater than or equal to NCORU, the subsequent time step is divided by TMODS. Enter a floating (real) value. The default is 2.0000e+00. USER--this parameter is used to trigger user specific routines. These parameters are provided as hooks into ProCAST. Contact ProCAST Technical Support to discuss the applicability of this parameter for your use. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

Changing from the TEMA solver to the CGSQ solver may improve the solve time in “larger” (500,000+ elements, 100,000+ nodes) models.

Related Topics

PAGE 3 - 194


RUN PARAMETERS

RUN PARAMETERS THERMAL Description

THERMAL is a push button in the RUN PARAMETERS menu. It provides the capability to specify the options used in thermal analyses.

Method

THERMAL is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the thermal parameters and, if applicable, units associated with a parameter.

The figure shown above illustrates the THERMAL dialog box. The THERMAL parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. CLUMP--specifies the capacitance matrix lumping factor. Enter: {0 to use consistent matrix, or 1 to use diagonal matrix} The default is 1. CONVT--specifies the convergence criterion for temperature. A value of around one degree is generally appropriate. Values larger than the mushy (liquidus--solidus) zone range are not recommended. Enter a floating (real) value. The default is 1.0000e+00. Select the units of temperature from: {C | F | R | K} CRELAX--specifies the heat capacity relaxation parameter. Enter a floating (real) value. The default is 1.0000e+00.


RUN PARAMETERS

LINSRC--specifies the source term linearization parameter for micromodels. This parameter may be used in conjunction with micromodels that control the evolution of the solid fraction and thus the release of latent heat. The default value of zero indicates that the heat generation will only appear in the right hand side source term. A value of one will give some contribution to the diagonal terms of the left hand side matrix. This improves numerical stability, but does require that the LHS be factored, which would normally happen anyway. Enter: {0 = no linearization, or 1 = for linearization of the source term} The default is 0. MFREQ--specifies the time step interval for writing micromodel results to the unformatted file. This parameter can be used to reduce the size of the micro results file, which can become quite large for problems with may nodes and time steps. Note that it is only possible to restart a run from one of the time steps that was written out. Enter an integer value. The default is 10. MICRO--specifies the micromodeling to be performed. The values specified in this parameter may be added together. This allows you to use a combination of micromodeling models in a single run. Enter an integer value based upon the following: {0 = no micromodeling, 1 = Eutectic ductile iron, 2 = Equiaxed dendrite, 4 = Stable/metastable eutectic with instantaneous nucleation, 8 = Stable/metastable eutectic with continuous nucleation, 16 = Eutectic gray/white iron, 32 = Eutectoid ductile iron, 64 = Eutectoid gray iron, 128 = Peritectic transformation, 256 = Delta/gamma, gamma/alpha, and gamma/cementite transformations, 512 = Scheil model for primary solidification, or 1024 = Solid Transformations} The default is 0.

PAGE 3 - 196


RUN PARAMETERS

MOBILE--specifies the Mobility factor. This parameter is the critical liquid fraction at which the free surface losses its mobility. Values between zero and one are acceptable. Piping depth can be quite sensitive to this parameter. Enter a floating (real) value. The default is 3.0000e-01. POROS--specifies the porosity calculations to be performed. Choose from: {0 for no porosity calculation, 1 to compute macro porosity, or 2 to compute porosity effects associated with a dissolved gas} The default is 1. QFREQ--specifies the time step interval for writing heat flux data to the unformatted results file. This parameter can be used to reduce the size of the prefixq.unf file. Heat flux results may not be of interest to everyone, so it may be desirable to minimize the size of this file. Enter an integer value. The default is 1. TFREQ--specifies the time step interval for writing temperature data to the unformatted results file. This parameter can be used to reduce the size of the prefixt.unf file, which can become quite large for problems with many nodes and time steps. Note that it is only possible to restart a run from one of the time steps that was written out. Enter an integer value. The default is 1. THERMAL--specifies the thermal analysis to be performed. Choose from: {0 for no thermal analysis. Solve flow equations alone, 1 to perform thermal analysis, using temperature as the primary variable, or 2 to perform thermal analysis, using enthalpy as the primary variable} The default is 1.


RUN PARAMETERS

TRELAX--specifies the temperature relaxation parameter. This is used for computing the initial guess for the temperature field in the predictor step. TRELAX should be greater than or equal to zero and less than or equal to one. Enter a floating (real) value. The default is 1.0000e+00. When you are satisfied with the parameters values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

The THERMAL parameters apply to every simulation wherein the energy equation is being solved.

Related Topics

RUN PARAMETERS

PAGE 3 - 198


RUN PARAMETERS

RUN PARAMETERS RADIATION Description

RADIATION is a push button in the RUN PARAMETERS menu. It provides the capability to specify radiation parameters and tolerances to be applied during the simulation.

Method

RADIATION is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the radiation parameters and, if applicable, units associated with a parameter.

The figure shown above illustrates the RADIATION dialog box. The RADIATION parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. ANGTOL--specifies the angle tolerance to be used with VFLIM. Radiation faces which are grouped using VFLIM tolerance are further differentiated by their solid angle. Enter a floating (real) value. The default is 4.5000e+01. ENCLID--specifies an enclosure identification number. This parameter is used in combination with VFDISP for updating view factors by a displacement interval. ENCLID indicates which enclosure set is to be tracked, in case all the enclosure elements are not moving at the same rate. Enter an integer value. The default is 0. EPTOL--specifies the emissive power tolerance to be used with VFLIM. Radiation faces which are grouped using VFLIM tolerance are further differentiated by their solid angle. Enter a floating (real) value. The default is 8.0000e-01.


RUN PARAMETERS

RDEBUG--specifies the user debug parameter for printing detailed view factor information. Various combinations of these files may be obtained by adding together these numbers. For example, RDEBUG = 7 gives all three files. Note that these files can be quite large, especially the prefix.vf. Enter an integer value based upon the following: {1 for face to face view factors after symmetrization, in the prefix.vf file, 2 for face to group view factors after symmetrization, in the prepfix.view file (necessary to see FACE TO GROUP in ViewCAST), or 4 for row sum errors before symmetrization, in the prefix.serr file (necessary to see ROW SUM ERRORS in ViewCAST} The default is 0. RFREQ--specifies the radiation update frequency. This provides a mechanism for recomputing the radiosities at some time step interval other than one. This is particularly useful if you are performing a filling transient along with the view factor radiation model. In this case, the time step size may be small due to the filing whereas the mold temperature may not be changing very rapidly. You can save some computational time by recomputing the radiosities at every tenth step, for example. Enter an integer value. The default is 1. VFDISP--specifies the displacement interval for updating view factors in the radiation model if there are moving relative surfaces. This is used in conjunction with ENCLID and will be used in preference to VFTIME if both are specified. Enter a floating (real) value. The default is 0.0000e+00. Choose the units of length from: {m | cm | mm | ft | in}. The default is m.

PAGE 3 - 200


RUN PARAMETERS

VFLIM--specifies the view factor limit. This parameter is used to agglomerate faces in the view factor calculations. This reduces the size of the radiosity matrix and speeds up the radiation calculations. VFLIM can be set to a fraction between zero and one. If one face occupies less than this fraction of the total view space, as seen from another face, the first face is combined with some others. A value of 0.01 is a good starting point. Enter a floating (real) value. The default is 0.0000e+00. VFTIME--specifies the time interval for updating view factors in the radiation model if there are moving relative surfaces. Enter a floating (real) value. The default is 0.0000e+00. Choose the units of time from: {sec | min}. The default is sec. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

The RADIATION parameters come into play when the view factor radiation model is employed.

Related Topics

RUN PARAMETERS


RUN PARAMETERS

RUN PARAMETERS FLOW Description

FLOW is a push button in the RUN PARAMETERS menu. It provides the capability to specify the flow solutions to be performed and the flow tolerances to be used during simulation.

Method

FLOW is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the flow parameters and, if applicable, units associated with a parameter.

The figure shown above illustrates the FLOW dialog box. The FLOW parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. ADVECTW--specifies the weighting of advection velocities and controls the degree of non-linearity of the momentum equations. ADVECTW can take on values between zero and one. Velocities at the last time step are used as the advecting velocities if a value of zero is used. Velocities at the current time step are used as the advecting velocities if a value of one is used. Numerical experience has shown that the accuracy of natural circulation flows can be enhanced by using a factor of 0.5. For most filling analyses, a value of zero works fine and requires much less computational time. Enter a floating (real) value. The default is 0.0000e+00.

PAGE 3 - 202


RUN PARAMETERS

COARSEC--specifies the constant coefficient for the coarsening equation. Enter a floating (real) value. The default is 8.8000e+00. COARSEP--specifies the power coefficient for the coarsening equation. Enter a floating (real) value. The default is 3.33000e-01. COMPRES--specifies whether this is an incompressible flow problem or a compressible flow problem. Choose from: {0 to specify an incompressible flow problem, or 1 to specify a compressible flow problem} The default is 0. CONVV--specifies the convergence criterion for velocity. The value given here is a fraction of the maximum velocity calculated at each step. Generally, .05 or 5% is appropriate. Enter a floating (real) value. The default is 5.0000e-02.

COUPLED--specifies whether the energy and fluid solutions should be coupled or decoupled within a time step. When the analysis is decoupled, the momentum and pressure equations are solved repeatedly until convergence. Subsequently, the energy equation is solved until convergence, assuming the flow field is fixed. With a coupled analysis, the energy equation is solved in the same loop with momentum and pressure. Both the momentum and temperature convergence criteria have to be met to terminate the loop. This method is more accurate, but usually takes more computational time. Choose from: {0 to decouple energy and fluid solutions withing a time step, or 1 to fully couple energy and fluid solutions within a time step} The default is 0.


RUN PARAMETERS

COURANT--specifies the courant limit on time step size. This parameter is only used for fluids problems. If COURANT is set to 1.0, the time step will be adjusted so that the fluid will advance no more than one element length. This is a fairly severe limit on time step size, but will give the most accurate results for filling transients. Acceptable results can usually be obtained with values between 10 and 50. For compressible flow problems, a COURANT limit of 0.5 is suggested. Enter a floating (real) value. The default is 1.0000e+00. EDGE--controls the algorithm for advecting the free surface front along the wall. Using the tangent component helps the flow to go around corners when the mesh is relatively coarse, but sometimes causes the fluid to flow preferentially along walls. Using the nearest free stream nodal velocity provides a mechanism for detaching the flow from the wall. If flow detachments are expected, then the nearest free stream nodal velocity option should be used. Choose from: {0 = use the tangent component of the nearest free stream nodal velocity, or 1 = use the nearest free stream nodal velocity} The default is 0. FFREQ--specifies the flow update frequency. This provides a mechanism for re-computing the velocities at some time step interval other than one. This might come into play if you were solving a conjugate heat transfer problem where the velocity field is changing on a longer time scale than the temperatures. This option is not appropriate for free surface problems. Enter an integer value. The default is 1.

PAGE 3 - 204


RUN PARAMETERS

FLOW--controls the use of fluid equations. Choose from: {0 do not solve fluid equations, 1 to solve fluid equations, 3 to solve fluid equations during filling, but switch over to thermal only analysis when the LVSURF fill limit is reached and NCYCLE = 1, 5 to calculate the potential flow analysis using the boundary element method, 9 to solve fluid equations during filling, but switch over to thermal only analysis when the LVSURF fill limit is reached and NCYCLE > 1} The default is 0 if there are no “F” materials. If “F” materials exist, the default is 1. FLOWDEL--specifies the delay time between the end of fill and a switch to a thermal only, FLOW = 3 simulation. This option is used in conjunction with velocity boundary conditions with active fill limits. The time delay buys time for the fluid to completely settle down in the casting before the thermal only phase begins. Enter a floating (real) value. The default is 1.0000e+20. Select the units of time from: {sec | min} The default is sec. FREESF--specifies the free surface model number to be used. Choose from: {1 = use the momentum dominated movement of free surface, rapid filling model, 2 = use the gravity dominated movement of free surface, slow filling model, or 3 = hybrid model, switch between 1 and 2 depending upon conditions} The default is 0.


RUN PARAMETERS

GAS--specifies whether or not to consider the trapped gas effects. If the option to consider trapped gas effects is chosen, trapped gas effects will be considered even when the model contains no vents, gas injection, or gas diffusion through the mold. When features normally found in a gas problem ( vents, injection, or gas diffusion through the mold ) are present in a model, GAS will be set automatically. Choose from: {0 to not consider trapped gas effects, or 1 to consider trapped gas effects} The default is 0. HEAD_ON--specifies the approach to be used when calculating gravitational term in the momentum equation for flow problems without free surfaces. Choose from: {0 = calculate as rho - rho_ref, or 1 = calculate as rho * g} The default is 0. HIVISC--specifies different solution methods for viscosity in the flow problem. Choose from: {0 = normal flow problem, 1= high viscous flow problem. To be used when the Reynolds number is less the one. This method only works for viscosity less than 104 poise. In this case, the advection terms are neglected, symmetric solvers are employed on the momentum equations, and large degrees of pressure relaxation are utilized, or 2 = very high viscous flow problem. To be used when the Reynolds number is less the one. This method is always preferred. In this case, the advection terms are neglected and momentum effect on implicitly included within a Poisson pressure equation. This option usually allows for much larger time steps than HIVISC = 1} The default is 0.

PAGE 3 - 206


RUN PARAMETERS

LVSURF--provides a way to switch from the filling transient to a mode where advection is due to buoyancy and shrinkage. LVSURF turns all inlets off. It is assumed thereafter that the free surface is perpendicular to the gravity vector. This allows the time step to increase significantly. The number represents the fraction of the total casting and rigging volume which is to be filled before changing modes. Enter a floating (real) value. The default is 9.80000e-01. MLUMP--specifies the mass matrix lumping factor. Choose from: {0.0 to use a consistent matrix, or 1.0 to use a diagonal matrix} The default is 1.00000e+00. NNEWTON--specifies whether the flow is newtonian or non-newtonian. Choose from: {0 to indicate Newtonian flow, or 1 to indicate non-newtonian flow, where viscosity is a function of shear rate} The default is 0. PINLET--specifies a pressure drive inflow. Setting PINLET to 1 indicates that all the pressure boundary conditions are also inflow boundary conditions. Use of this option allows one to avoid using thin filled regions at the inlets of pressure driven problems. It allows for filling of metal without having an initial layer of fluid. Enter an integer value of 0 (off) or 1 (on). The default is 0. PLIMIT--specifies the pressure cutoff limit. You can use this parameter to turn off an inlet velocity when the back pressure exceeds the given value. This is useful particularly in cases where cold shuts are occurring. Otherwise, the program will keep trying to force more mass into the fluid region, even though there is no place for it to go, and the pressure will continue to rise. Enter a floating (real) value. The default is 1.00000e+20. Choose the pressure units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} The default is N/m**2.


RUN PARAMETERS

PREF--specifies the pressure which is to be subtracted from any boundary condition pressure in order to convert an absolute pressure into a gauge pressure. This parameter comes into play when: (1) there is trapped gas, (2) a pressure boundary condition drives the flow, (3) there are vents, and/or (4) there is gas injected. For example, if the pressure boundary condition drives the flow at a gauge of 1 atmosphere, the boundary condition is set to 2 atm. PREF should be set to 1 atm. Enter a floating (real) value. The default is 0.00000e+00. Choose the pressure units from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} The default is N/m**2. PRELAX--specifies the pressure relaxation factor. PRELAX, to have an effect, should be greater than zero and less than one. If it is left to the default value of one, ProCAST will automatically compute an appropriate relaxation factor. Enter a floating (real) value. The default is 1.00000e+00. SPLIT--This parameter is obsolete. TPROF--This parameter indicates that a thermal boundary layer profile is used at the wall for the energy equation with advection. This has been found to reduce false diffusion errors. Choose from: {0 = do not use boundary layer profile, or 1 = use boundary layer profile} Enter an integer value. The default is 1. TSOFF--This parameter specifies the time at which to switch off the flow solution. For example, TSOFF 1 42, indicates that the flow solution will be turned off 42 seconds into the simulation. If a cyclic analysis is being performed, then the flow solution will be turned off 42 seconds into each cycle. Choose from: {0 = turns this option off, or a real value sets the time} Enter a floating (real) value. The default is 0.00000e+00. Choose the time units from: {sec | min}. The default is sec. VFREQ--specifies the time step interval for writing velocity and PAGE 3 - 208


RUN PARAMETERS

pressure results to the unformatted files. This parameter can be used to reduce the size of these results files, which can become quite large for problems with many nodes and time steps. Note that it is only possible to restart a run from one of the time steps that was written. Only the steps that are written can be viewed with post-processing. Enter an integer value. The default is 1. WSHEAR--specifies whether or not the wall shear formulation will be used. The wall shear formulation will convert no-slip boundary conditions into wall traction conditions. Choose from: {0 to indicate that wall shear formulation will not be used, or 1 to indicate wall shear formulation will be used} The default is 0. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

The FLOW parameters allow you to specify the type of fluids analysis to be performed. They also allow you to make adjustments to control some trade-off between speed and accuracy.

Related Topics

RUN PARAMETERS


RUN PARAMETERS

RUN PARAMETERS TURBULENCE Description

TURBULENCE is a push button in the RUN PARAMETERS menu. It provides the capability to specify turbulence parameters to be applied during the simulation.

Method

TURBULENCE is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the turbulence parameters.

The figure shown above illustrates the TURBULENCE dialog box. The TURBULENCE parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. CMU--specifies the proportionality constant used in the turbulent viscosity equation. See Equation C.6.1 in Appendix C. Enter a floating (real) value. The default is 9.0000e-02. CONE--specifies the proportionality constant used in the production of turbulent energy dissipation. See Equation C.5.1 in Appendix C.

Enter a floating (real) value. The default is 1.44000e+00. CTWO--specifies the proportionality constant used in the destruction of turbulent energy dissipation. See Equation C.5.1 in Appendix C. Enter a floating (real) value. The default is 1.92000e+00. KAPPA--specifies the Von Karman’s constant, usually taken as 0.4 Enter a floating (real) value. The default is 4.0000e-01.

PAGE 3 - 210


RUN PARAMETERS

SIGMAE--specifies the diffusivity modifier used in the turbulent energy dissipation transport equation. See Equation C.5.1 in Appendix C. Enter a floating (real) value. The default is 1.3000e+00. SIGMAK--specifies the diffusivity modifier used in the turbulent kinetic energy transport equation. See Equation C.4.1 in Appendix C. Enter a floating (real) value. The default is 1.0000e+00. TBRELAX--specifies the turbulence relaxation parameter. Enter a floating (real) value. The default is 1.0000e+00. TURB--specifies whether the turbulent flow model is turned on or off. A model started with TURB = 1 can be restarted at a later time with TURB = 0. This allows laminar conditions to be considered during mushy or natural circulation flows. Once TURB has been set to zero, the turbulence model can not be restarted at a later time. Setting TURB to one for a flow problem which has no turbulence boundary conditions assigned is okay; ProCAST will automatically define them. Enter: {0 to turn the turbulent flow model off, or 1 to turn the turbulent flow model on} The default is 0. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

The default TURBULENCE parameters are used in the standard --- model, but they are all adjustable.

Related Topics

RUN PARAMETERS


RUN PARAMETERS

RUN PARAMETERS STRESS Description

STRESS is a push button in the RUN PARAMETERS menu. It provides the capability to specify stress parameters and tolerances to be applied during the simulation.

Method

STRESS is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the stress parameters and, if applicable, options associated with a parameter.

The figure shown above illustrates the STRESS dialog box. The STRESS parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. CONVS--specifies the convergence criterion for the stress calculation. Enter a floating (real) value. The default is 1.0000e-02. SFREQ--specifies the time step interval for writing stress results to the unformatted files. This parameter can be used to reduce the size of these files, which can become quite large for problems with many nodes and time steps. Note that it is only possible to restart a run from one of the time steps that was written. This also controls the frequency for performing stress analysis. Enter an integer value. The default is 1.

PAGE 3 - 212


RUN PARAMETERS

STRESS--specifies whether the stress calculation is turned on or off. Enter: {0 to turn the stress calculation off, or 1 to turn the stress calculation on} The default is 0. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

The default STRESS parameters are those normally used in most stress models, but they are all adjustable.

Related Topics

RUN PARAMETERS


RUN PARAMETERS

RUN PARAMETERS ELECTROMAGNETIC Description

ELECTROMAGNETIC is a push button in the RUN PARAMETERS menu. It provides the capability to specify electromagnetic parameters to be applied during the simulation.

Method

ELECTROMAGNETIC is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the electromagnetic parameters and, if applicable, options associated with a parameter.

The figure shown above illustrates the ELECTROMAGNETIC dialog box. The ELECTROMAGNETIC parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. CFREQ--specifies the driving frequency ( hertz ) of the current which flows inside the induction coil. Enter a floating (real) value. The default is 0.0000e+00. EFREQ--specifies the time step interval for writing electromagnetic results to the unformatted files. This parameter can be used to reduce the size of these files, which can become quite large for problems with many nodes and time steps. Note that it is only possible to restart a run from one of the time steps that was written out. Enter an integer value. The default is 1. EM--specifies whether the electromagnetic calculation is turned on or off. Enter: {0 to turn the electromagnetic calculation off, or 1 to turn the electromagnetic calculation on} The default is 0.

PAGE 3 - 214


RUN PARAMETERS

EMITER--specifies the number of solver iterations allowed when solving the magnetic potential equations. Enter an integer value. The default is 100. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

To run electromagnetics EM must be set to 1 and CFREQ has to be given a realistic value.

Related Topics

RUN PARAMETERS


RUN PARAMETERS

RUN PARAMETERS INVERSE Description

INVERSE is a push button in the RUN PARAMETERS menu. It provides the capability to specify inverse parameters and tolerances to be applied during the simulation.

Method

INVERSE is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the inverse parameters.

The figure shown above illustrates the INVERSE dialog box. The INVERSE parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. CONV--specifies the convergence tolerance. The convergence will be reached when the variation, between two iterations, of each property will be smaller than this value. Enter a floating (real) value. The default is 5.0000e-02. ITERMAX--specifies the maximum number of iterations before the calculation is terminated. In some cases, if the tolerance is too small, the variation of the beta values will not be within the tolerance, although the calculation would have converged. A value between 15 and 30 iterations is reasonable. Enter an integer value. The default is 15. SIGMA--specifies the weighting coefficient for temperature. The weighting coefficient for temperature should be kept small in order to have good convergence. A value of 0.1( C has proven to give good results. Enter a floating (real) value. The default is 1.0000e-01.

PAGE 3 - 216


RUN PARAMETERS

TAU--specifies the time constant for the filtering of measurements. In order to remove small perturbations which might occur during the measurements, the curves are filtered using the time constant. The units of TAU are seconds. Enter a floating (real) value. The default is 1.0000e+00 VARB--specifies the variation of each beta value during an iteration. During an iteration, the beta values will be perturbed one after the other in order to determine the sensitivity coefficients of each property. To do so, each beta value will be changed by a given amount corresponding to the value of varb times the beta value. Values of varb between 0.05 and 0.2 are convenient and correspond to a variation of 5 to 20% of the beta values. Enter a floating (real) value. The default is 1.0000e-01. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

A display window is displayed in which you must enter the node numbers or node coordinates which correspond to the location of the measurement points. The order of this list should correspond to the order of the measured curves in the measurement file, prefixim.dat. The proper sequencing of these lists is mandatory because the calculated and measured curves will be compared in the inverse calculation and should correspond to the identical location.

Related Topics

RUN PARAMETERS


RUN PARAMETERS

RUN PARAMETERS CAFE Description

CAFE is a push button in the RUN PARAMETERS menu. It provides the capability to specify parameters and tolerances to be applied to the CAFE model during the simulation. Editor’s Note: The CAFE capability has not yet been implemented in ProCAST.

Method

CAFE is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the CAFE parameters and, if applicable, units associated with a parameter.

The figure shown above illustrates the CAFE dialog box. The CAFE parameters and the available options for each parameter will be discussed here. For convenience in presentation, they will be presented in alphabetical order. CELLSZ--is the length dimension for the cellular automata cells. Enter a floating (real) value. The default is 0.0000e+00. Select the units of measure from: {m | cm | mm | ft | in}. The default is m. ISEED--is the initialization parameter for random number generation. Enter an integer value. The default is 0. When you are satisfied with the parameters and their values, click on the APPLY push button. This will store the values you have entered in the prefixp.dat file. You may close this display without saving the parameters you entered or changes you may have made by clicking the CANCEL push button. Remarks

None.

Related Topics

RUN PARAMETERS

PAGE 3 - 218


USING DATACAST

CHAPTER 4 USING DataCAST Description

DataCAST reviews the total model, performs extensive error checking, and converts all the units into standard CGS. DataCAST also creates a summary file which describes the complete analysis model. This summary file provides one form of model documentation. When DataCAST has completed its error checking, it creates the binary files which will be read by ProCAST as the simulation input.

Method

DataCAST runs in a either a Unix or a Microsoft Windows NT session window. DataCAST can be started using the following command line instruction at the session window prompt or the Run Dialog Window: datacast {prefix} [-u | -v | -d ] ENTER Prefix is a required parameter and you should enter the name you want given to this project. DataCAST may also be started from the EXECUTE menu in the PCS screen. -u is an update option. This recreates the model files without reinitializing the results. -v is a command line option which specifies verbose output in the error messages. By default, nodes and elements are no longer printed in error messages. -d is a command line option which specifies that the determinant of the Jacobian should be checked. This identifies bad elements.

Remarks

If you start a DataCAST session without the prefix parameter shown above, you will be given a message in the session window and prompted to enter a prefix. The formatted file containing the description of the problem is the prefixd.dat file. This is the file which is read by DataCAST. The complete file format and record description for this file may be found in Appendix D.

USING DATACAST, PAGE 4 - 1

USING DATACAST

If DataCAST encounters any errors in the model, it will display appropriate messages on the workstation screen. These error messages are also written into the formatted file prefixd.out. When DataCAST has completed its processing, the formatted file prefixd.out will be available for viewing. This file contains a log of all the geometry, material properties, and boundary/initial conditions converted into CGS units, and any error messages. Temperatures are in units of degrees Kelvin. If errors do occur, they should be corrected before going on to run ProCAST. Related Topics

PAGE 4 - 2


prefixd.dat File Format (Appendix D)

USING PROCAST

CHAPTER 5 USING ProCAST Description

ProCAST performs the simulation analysis.

Method

ProCAST runs in a either a Unix or a Microsoft Windows NT session window. ProCAST can be started, on the Unix platform, using the following command line instruction at the session window: procast {prefix} [ & ] ENTER Prefix is a required parameter and you should enter the name you want given to this project. ProCAST can be started, on the NT platform, using the following command line instruction at the session window prompt or the Run Dialog Window: prosolve {prefix} [ & ] ENTER ProCAST may also be started from the EXECUTE menu in the PCS screen. & is a command line option which specifies that ProCAST will be run in the batch or background mode.

Remarks

If you start ProCAST without the prefix parameter shown above, you will be given a message in the session window and prompted to enter a prefix. ProCAST can be run either in the foreground or in batch mode. Since the main number crunching occurs in ProCAST, these runs are relatively long and batch mode is usually preferable. When the run has finished, the results will be contained in a variety of files. These files are described in Appendix B: ProCAST File Usage. The prefix.out file contains useful information about the run such as the memory usage, the convergence behaviour, the iterations and cpu times taken by the solvers, etc. This can be helpful in identifying problems in an analysis. You can view the formatted file prefixp.out, which can have nodal values of temperature, pressure, velocity and heat flux. The various unformatted results files that have the unf extension are read by PostCAST and ViewCAST for postprocessing. There is a small utility program which can be run to report the status of USING PROCAST, PAGE 5 - 1

USING PROCAST

any ProCAST analysis which is currently running or which has completed its processing. This utility may be started by opening a Unix session window and typing the following command at the session window prompt: prostat {prefix} ENTER ProSTAT will provide information about the simulation which includes: number of time steps completed, total simulated time, current time step size, percent filled, solid fraction, cycle number, elapsed CPU time, and elapsed wall clock time for the job prefix. An example of a ProSTAT Report is shown here.

NUMBER OF STEPS = 10 SIMULATED TIME = 1.023000 SECONDS TIME STEP = 0.512000 SECONDS PERCENT FILLED = 100.000000 % SOLID FRACTION = 0.000000 % CYCLE 1 IS 0.000000 % COMPLETE CUP TIME = 0.070000 SECONDS SYSTEM TIME = 0.080000 SECONDS WALL CLOCK TIME = 1 SECONDS STEP COMPLETED ON Dec 18 1996 AT 17:30:03

Related Topics

PAGE 5 - 2


ProCAST File Usage (Appendix B)

USING POSTCAST

CHAPTER 6 USING PostCAST Description

PostCAST provides the post-simulation capability to extract data from the simulation results data files and format it for further analysis. PostCAST provides the capability to graphically display temperature, velocity, pressure, fraction solid, and stress versus time results. PostCAST files may be displayed graphically using ViewCAST, PATRAN, or IDEAS.

Method

PostCAST runs in a either a Unix or a Microsoft Windows NT session window. PostCAST can be started using the following command line instruction at the session window prompt or the Run Dialog Window: postcast {prefix} [ -f filename ] ENTER Prefix is a required parameter and you should enter the name you want given to this project. PostCAST may also be started from the EXECUTE menu in the PCS screen. -f filename is a command line option for batch processing instructions. The filename specifies the file containing the instructions. This option currently will do just a subset of the total capabilities of PostCAST.

Remarks

If you start a PostCAST session without the prefix parameter shown above, you will be given a in the session window and prompted to enter a prefix. When PostCAST is activated, it will display a work space with a gray (by default) background, the UES logo in the lower right-hand corner, and a Main Function Banner across the top of the work space. You may use the push buttons in this banner to navigate through the functions of PostCAST. These functions are: OPTIONS, FORMAT, STEPS, UNITS, MATERIALS, and EXIT Each of these functions are described in the following pages. They are presented in the order shown above which corresponds to their left-toright placement in the Function Banner.

USING POSTCAST, PAGE 6 - 1

USING POSTCAST

The following information can be provided by PostCAST. • Temperature results at each stored time step, • Pressure results at each stored time step, • Velocity results at each stored time step, • Turbulence quantities at each stored time step, • Heat flux results at each time stored step, • Time to reach a given temperature (Isochrons), • Temperature, fraction solid, pressure, velocity, and stress versus time results for various nodes, • Solidification rate, cooling rate, and temperature gradient results which can be combined into a factor indicative of microscopic features, • Niyama or LCC criteria, • R, G, L criteria, • SDAS, • Alpha case, • Feeding length at the end of solidification, and • Row sum errors from the radiation model. Related Topics

PAGE 6 - 2


OPTIONS, FORMAT, STEPS, UNITS, MATERIALS, EXIT

OPTIONS

OPTIONS Description

OPTIONS is a push button in the Main Function Banner. This function of PostCAST enables you to select options to be applied during the post processing functions. These options will influence the manipulation of results obtained from the ProCAST simulations and solutions. When you activate the OPTIONS push button, a menu is opened which will allow you to work with specific aspects of the simulation results. The functions available from this menu will be discussed in this section.

Method

OPTIONS is activated by clicking on it. The initial menu is shown here. When you select a function from this menu, PostCAST will display additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting information about the options and their alternative attributes. You may leave the OPTIONS function by clicking another push button in the Main Function Banner.

Remarks

The OPTIONS function of PostCAST provides the capability to select portions of the results of the simulation for further analysis, examination or processing. For example, this selection process allows you to select thermal or velocity results for every tenth node, every other node or every 50th node for viewing and analysis. The PostCAST options will influence the manipulation of results obtained from the ProCAST simulations and solutions. Other functions available from the PostCAST Main Function Banner, such as MATERIALS or STEPS, may affect the parameters you specify with these OPTION parameters. For example, if you are interested in looking at only one material, you should designate that material using the MATERIALS push button in the Main Function Banner before specifying OPTIONS. Similarly, if you are interested in examining the results from one time step, you should designate that time step using the STEPS push button in the Main Function Banner before specifying OPTIONS.

Related Topics


OPTIONS

OPTIONS X-Y PLOT Description

X-Y PLOT is a push button in the OPTIONS menu. It provides the capability to plot the Temperature, Fraction Solid, Pressure, Velocity, and Stress and Strain versus time results of the simulation. You may select or specify the nodes to be displayed in the plots. Using the OPTIONS menu, X-Y PLOT also provides the capability to customize, to an extent, the appearance of the resulting plots.

Method

X-Y PLOT is activated by clicking on it. This results in the immediate action to display a sub-menu of push buttons which list the types of plots for which nodal selections may be made. The figure shown here illustrates this submenu. When you select an option from this menu, the background of that push button is highlighted in red and an additional sub-menu will be displayed. This sub-menu provides the capability to specify the method by which nodes are to be selected for the Temperature, Fraction Solid, Pressure, Velocity, and Stress plotting. Graphically, the sub-menu for specifying the nodal values is the same when you choose any option except temperature. When you choose TEMPERATURE, the sub-menu includes the EXTERNAL option. The example shown here illustrates this sub-menu display after choosing the Temperature option. Notice that the TEMPERATURE push button has been highlighted. Each of these nodal selection push button options, Interval, Nodes, Options, and External, will be discussed in this section. For convenience they will be presented in alphabetical order.

PAGE 6 - 4


OPTIONS

You may close this display and move to another function of PostCAST or to another function of OPTIONS by clicking the appropriate Main Function Banner or Menu push button respectively. EXTERNAL PostCAST allows you to read temperature - time data from other sources, such as thermocouples, to plot on the same picture as the simulation results. The EXTERNAL push button allows you to specify the file names containing this external data. When you click on the EXTERNAL push button in the sub-menu, PostCAST displays the file input display as shown in the figure here. Entering data in the table is done by first selecting the desired table entry. You select a table entry by clicking on the desired entry. If the table is empty, select the area in the first row. This is illustrated in the figure shown here. Once a table entry is selected the background of that entry will change to red and the cursor will be placed in the Enter File Name input box. If the entry contains data, the data will be displayed in the Enter File Name input box. You may then enter or change the file name in the input box. You may enter up to ten different file names. If the file is not in the current directory, then you need to provide the full path name and file name. When you are satisfied with the new data, press ENTER. This will place the value in the highlighted table entry and move the cursor to the next available table entry. External File contents and format--the first row of an external file should contain the number of thermocouples or temperature values given at each time. This should be followed by the thermocouple identification numbers which will be used to label the curves in the temperature plot. Subsequent rows in the file should have a time value and temperature for each thermocouple. All data is read in free format and should be separated by a space between each value. You may have as many thermocouple results as you can fit on one line. USING POSTCAST, PAGE 6 - 5

OPTIONS

Up to 5000 time levels may be given in one file. INTERVAL PostCAST allows you to specify a node number interval for plotting. For example, if you wanted to see the cooling curve for every tenth node, you would enter an interval of 10. The default is one, or every node. The INTERVAL option is very useful for a quick look at the thermal results of the simulation. It can tell you if the simulation is behaving properly or if the results are becoming erratic, which may indicate an error in the problem’s setup. When you click on the INTERVAL push button in the sub-menu, PostCAST displays an Edit Value input box as shown in the figure here. To enter an interval value, place the cursor in the Edit Value input line, type the desired integer value, and click on the APPLY push button.

You may close this display without specifying or changing the interval value by clicking the CANCEL push button.

PAGE 6 - 6


OPTIONS

The example shown here is an X-Y Plot of the temperature of a casting where the temperature of every 100th node was selected using the INTERVAL option. NODES PostCAST allows you to specify node numbers for plotting. When you click on the NODES push button in the sub-menu, PostCAST displays the Nodal Values input display as shown the figure here. Entering data in the table is done by first selecting the desired table entry. You select a table entry by clicking on the desired entry. If the table is empty, select the area in the first row. This is illustrated in the figure shown here. If the table contains nodal values and you want to add another value, use the scroll bar, if necessary, to move to the end of the table and select the first empty area. Once a table entry is selected the background of that entry will change to red and the cursor will be placed in the Edit Value Input Box. If the entry contains data, the data will be displayed in the Edit Value Input Box. You may then enter or change the node number in the Edit Value Input Box. When you are satisfied with the new data, press ENTER. This will place the value in the highlighted table entry and move the cursor to the next available table entry. Node Selection Crosshairs

Node Selection Crosshairs

Node to be Selected


OPTIONS

You may also select the nodes graphically. Click on the XYZ push button in the Nodal Values input display. This will display a 2D or 3D view of the model in the Work Window Pane depending upon the geometry of your model. For 2D you may enter the coordinates for the node of interest to you or you may move the cursor to a desired node in the geometry and click on the left mouse button. When you click near or on a node in the geometry, PostCAST will display green Node Selection Crosshairs to help you isolate the node and will display the node’s coordinates in the appropriate input line. This is illustrated in the figure shown here. If you press and hold the left mouse button in the Work Window pane, you can “drag” the crosshairs to another position in the display. When you release the mouse button the node closest to the cursor will be selected. For 3D models, PostCAST displays a small window with three slider bars. You can move the slider bars to control the position of the orthogonal cutting planes. Or you may enter the coordinates as described above. When you are satisfied with the selected node, click on the APPLY push button. This will store the nodal value in the Nodal Values input display. You may use either or both the Edit Value input line and XYZ coordinate selection techniques to enter node numbers. When you are satisfied with all of the nodal values, click on the EXECUTE push button in the Nodal Values input display. This will result in PostCAST selecting the appropriate nodal data for plotting and display the plot. You may close the Nodal Values input display by clicking the CANCEL push button. Node selection--allows you to isolate and clearly display the thermal behavior of a few selected points in the casting. You may enter up to 100 different node numbers in the Nodal Values input display.

PAGE 6 - 8


OPTIONS

OPTIONS OPTIONS in this sub-menu provide the capability to customize, to an

extent, the appearance of the resulting plots. It also allows you to perform Cooling Curve Analyses. When you click on the OPTIONS push button a sub-menu is displayed. The contents of this sub-menu will be determined by the button you clicked in the X-Y menu. The figure shown here illustrates the options which are available when you select TEMPERATURE. It also illustrates how PostCAST graphically indicates the context of the options you are specifying. When you select an initial menu option other than TEMPERATURE, the OPTIONS sub-menu will contain only the COLOR, AUTOMATIC, and FEATURE ANGLE choices. Each push button in this sub-menu affects the appearance of the plots or is used to perform the Cooling Curve Analysis. Each of these sub-menu push buttons will be discussed in this section. COLOR--is a rotary toggle switch which allows you to specify the respective colors for the background and the plotted results. By default, the cooling curves are drawn with various colors. However, you may find it useful to draw these plots in black on a white background or in white on a black background. Successive clicks on this toggle switch will cycle through the alternatives. The options are: {COLOR | BLACK/WHITE | WHITE/BLACK}. The default is COLOR.


OPTIONS

AUTOMATIC/MANUAL--is a toggle switch which allows you to specify the method to be used for scaling the Y axis in the plot. By default, the temperature (or any other quantity) on the Y axis is scaled automatically to the minimum and maximum values that were found among the time steps selected for display. When you click on the AUTOMATIC toggle switch, a Text Input dialog box is displayed. As shown in this figure, you may input the minimum and maximum values you want to use for scaling the Y axis in the resulting plot. Successive clicks on this push button will toggle between the AUTOMATIC and MANUAL methods for scaling the Y axis. FEATURE ANGLE--determines which element edges of a mesh will appear in the geometry plot while selecting XYZ coordinates. When you click on the FEATURE ANGLE push button, an angle input dialog box containing a slider bar is displayed. As shown in this figure, you may select the degree of the feature angle by moving the slider in the horizontal scroll bar. You may move the slider by clicking the left mouse button on either of the directional arrows--moving the slider one degree at a time, by clicking the left mouse button in the slide track--jumping the slider a number of degrees at a time, or by clicking on and dragging the slider--selecting the degree in a continuous manner proportionate with the extent of the mouse movement. The edge between two element faces will be drawn if the angle between the normals of the two faces is greater than or equal to the feature angle you select. A feature angle of zero will cause all element edges to be displayed. The angle selected may be between zero and 180 degrees. When you are satisfied with the Feature Angle specified, click on the SAVE push button below the slider bar to save the selected value and close the display.

PAGE 6 - 10


OPTIONS

DT vs TIME--is used to plot the differences between two thermal histories as a function of time. This plot is available only from the TEMPERATURE X-Y PLOT option. One of the timetemperature data sets used in this comparison enters via an EXTERNAL file, as described above. The other data set is taken from the numerical results for a specified node number. You may specify the node number using the NODES capability described above. To select this plot, click on the DT vs TIME toggle switch in the menu. When it has been selected, the checkbox will be highlighted in burgundy. Successive clicks on this menu item will toggle DT vs TIME between on and off. To view the plot, select DT vs TIME, click on the NODES push button and then select the EXECUTE function a after nodal value has been assigned. DT vs TIME and DT vs TEMP are mutually exclusive. If you select DT vs TIME, DT vs TEMP will be deselected and vice versa. DT vs TEMP--is used to plot the differences between two thermal histories as a function of temperature. This plot is available only from the TEMPERATURE X-Y PLOT option. This capability works like the DT vs TIME option, except the resulting plot will be as a function of temperature. You may specify the node number using the NODES capability described above. To select this plot, click on the DT vs TEMP toggle switch in the menu. When it has been selected, the checkbox will be highlighted in burgundy. Successive clicks on this menu item will toggle DT vs TEMP between on and off. To view the plot, select DT vs TEMP, click on the NODES push button and then select the EXECUTE function after a nodal value has been assigned.


OPTIONS

1st DERIVATIVE--is a toggle switch used to indicate that you want the first derivative curve drawn when the cooling curve is plotted. When selected, the checkbox will be highlighted in burgundy. Successive clicks on this menu item will toggle 1st DERIVATIVE between on and off. This plot is available only from the TEMPERATURE X-Y PLOT option. To view the plot, click on the NODES push button and then select the EXECUTE function after a nodal value has been assigned or an external file has been specified. You will be asked to choose both the start and the end of solidification. You may do so by using the left mouse button to drag the cursor to the appropriate locations on the first derivative curve. You will also be asked to enter the specific heat of the metal. You may enter an average constant value of the specific heat (in c.g.s. units). Generally, the onset of solidification is the temperature corresponding to maximum in the second derivative curve. The temperature value corresponding to the minimum in the first derivative curve (beyond the temperature corresponding to maximum in first derivative curve) is the point where solidification ends. This is explained, in more detail, in the Remarks Section below under Cooling Curve Analysis. 2nd DERIVATIVE--is a toggle switch used to indicate that you want the second derivative curve drawn when the cooling curve is plotted. When selected, the checkbox will be highlighted in burgundy. Successive clicks on this menu item will toggle 2nd DERIVATIVE between on and off. This plot is available only from the TEMPERATURE X-Y PLOT option. To view the plot, click on the NODES push button and then select the EXECUTE function after nodal values have been assigned or external files have been specified. GRID--is a toggle switch used to indicate whether or not you want to have a grid displayed when the curves are plotted. When selected, the checkbox will be highlighted in burgundy. Successive clicks on this menu item will toggle GRID between on and off. This function is discussed in further detail in the Remarks Section below under Cooling Curve Analysis. To view the plot, click on the NODES push button and then select the EXECUTE function after nodal values have been assigned.

PAGE 6 - 12


OPTIONS

SMOOTH--provides the capability to smooth an array of points which are read from an external file. Typically the raw timetemperature data read by a thermocouple contains a lot of noise.. The resulting cooling curve needs to be smoothened. This push button executes a routine to smooth an array of points that are in order of increasing abscissas. This plot is available only from the TEMPERATURE X-Y PLOT option You activate the SMOOTH capability by clicking the SMOOTH push button. This will display an Edit Value input box. As shown in this figure, this box allows you to specify the amount of smoothing desired. The amount of smoothing to be performed is specified as the number of points over which the data needs to be smoothed. Zero gives no smoothing. Any value larger than about half of the total number of data points will make the output featureless. Typically, a reasonable value will be between 5 and thirty. To enter a value, place the cursor in the Input Line, type a integer value, and click on the APPLY push button. This function is discussed in further detail in the Remarks Section below under Cooling Curve Analysis.

Remarks

The discussion of syntax and options for Interval, Nodes, and Options above may be applied to the X-Y PLOT of Temperature, Fraction Solid, Pressure, and Velocity. External, DTA, first and second derivatives and smoothing only apply to temperature. Cooling Curve Analysis--input is the raw time-temperature data as typically read by a thermocouple placed at a certain location of a casting. It is read into PostCAST from an external file. Alternatively, cooling curve analysis can also be done on simulated nodal temperature data. Usually, one thermocouple trace is processed at a time. PostCAST’s routine for smoothing cooling curve data, which typically contains a lot of noise, uses a Fast Fourier Transform to low pass filter the data. Based upon your input to specify the number of points over which the smoothing is to be done, a natural cubic spline algorithm is used to interpolate a curve through these smoothened data points. The first and second derivative of temperature are also displayed. The temperature value corresponding to the maximum in the USING POSTCAST, PAGE 6 - 13

OPTIONS

second derivative curve is called TEN. The time value corresponding to TEN is the start of the solidification. The temperature value corresponding to the maximum in the first derivative curve is called MXRRES. The temperature value corresponding to the minimum in the first derivative curve beyond the time value corresponding to MXRRES, is called TES. The time value corresponding to TES gives the time for end of solidification. After you have selected the 1st DERIVATIVE and/or 2nd DERIVATIVE options, the plots have been drawn, and you have chosen both the start and the end of solidification on the first derivative curve, a cubic spline curve will be plotted between those two points, which is basically the derivative of the zero curve. Also, you will be asked to enter the specific heat of the metal. You may enter an average, constant value of the specific heat. The area under the first derivative curve and the derivative of the zero curve between times corresponding to TEN and TES gives the latent heat of transformation, which is calculated by numerical integration. The latent heat value is then printed on the screen in cgs units, i.e., cal/gm. The cooling curve analysis technique can be easily used for the determination of fraction of solid. By calculating the cumulative area between the first derivative curve and the derivative of the zero curve between TEN and TES as a fraction of the total area between these curves, the values of the total fraction of solid evolved as a function of time are obtained. When this curve is differentiated with respect to time, two distinct mechanisms are noticed. The time rate of the evolution of the fraction of solid has two parts: one is for the initial nucleation and the other is for bulk solidification. Usually the rate of change of fraction of solid curve can be assumed to be a linear function in time. The coefficients of this curve can easily be determined. By taking a series of cooling curves at different locations in a casting and processing each one of them, one can evaluate the derivative of a fraction of solid curve as a function of time for each curve. Then considering the effect of the cooling rate, a general time derivative of fraction of solid curve can be constructed as a function of time and cooling rate. In general, this cooling curve analysis technique can be used as a process control tool. It can be used to determine the occurrence of various phases during solidification and solid state transformation of almost all alloys. It can also be used effectively for control of inoculation in gray iron. The effect of PAGE 6 - 14


OPTIONS

inoculation on the formation of austenite can be easily determined using this technique because the amount of austenite formed can be determined. Also, carbon equivalent information can be predicted. This technique can be used to obtain the latent heat of solidification of an unknown material, which is a good technique for characterization of new materials. Also, by using this technique, one can determine the liquidus and solid temperatures precisely. In addition, any precipitation of phases during the cooling process can be easily determined. The mathematical description of this process can be found in Appendix C, Mathematical Formulations. Related Topics

TABLE MAINTENANCE, Mathematical Formulations


OPTIONS

OPTIONS GEOMETRY Description

GEOMETRY is a push button in the OPTIONS menu. It creates an ASCII file containing the nodal coordinates and element connectivities as they are extracted from the prefixg.unf file.

Method

GEOMETRY is activated by clicking on it. This builds the ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.

PostCAST displays an information window to indicate that the file has been built successfully. The figure shown here illustrates this type of information window. Notice that the name of the file built is displayed in this information window. You may close this display and move to another function of PostCAST or to another function of OPTIONS by clicking the appropriate Main Function Banner or Menu push button respectively. Remarks

This geometry file represents the final configuration of the model as it goes into ProCAST. Accordingly, it will contain any new nodes which have been generated and any renumbering of elements and nodes that may have occurred in PreCAST or DataCAST.

Related Topics

PAGE 6 - 16


OPTIONS

OPTIONS RADIATION FACE Description

RADIATION FACE is a push button in the OPTIONS menu. It creates an ASCII file containing the nodal coordinates and element connectivities of only the faces that are participating in a view factor radiation model.

Method

RADIATION FACE is activated by clicking on it. This results in the immediate action to build the ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.


This file is useful for identifying any gaps in the casting or enclosure which would cause large row sum errors in the view factor matrix.

Related Topics


OPTIONS

OPTIONS TEMPERATURE Description

TEMPERATURE is a push button in the OPTIONS menu. It provides the capability to extract temperature results from the prefixt.unf file, which is a binary file, and write them to an ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.

Method

TEMPERATURE is activated by clicking on it. This results in the immediate action to display a sub-menu of push buttons which are the methods you may use to designate the time step levels to be included in the output file. The figure shown here illustrates this sub-menu. When you select an entry from this table by clicking the desired option, the background of that push button is highlighted in red. When you select the SPECIFY STEPS or SELECT STEPS options from this menu, additional input dialog tables will be opened. These tables provide the capability to specify time step levels to be included in the output file. Each of the time step selection push button options, Interval, Specify Steps, and Select Steps, will be discussed in this section. For convenience they will be presented in alphabetical order. You may close this display and move to another function of PostCAST or to another function of OPTIONS by clicking the appropriate Main Function Banner or Menu push button respectively.

PAGE 6 - 18


OPTIONS

INTERVAL If you choose INTERVAL, the time step levels will be determined based upon the values entered in the STEPS function of the Main Function Banner. The interval chosen must be a multiple of TFREQ, which controls the frequency of output to the temperature results file.

PostCAST displays an information window to indicate that the file has been built successfully. The figure shown here illustrates this type of information window. Notice that the name of the file built is displayed in this information window. SPECIFY STEPS SPECIFY STEPS provides the capability to directly input the desired time step numbers. When you click on the SPECIFY STEPS push button in the submenu, PostCAST displays the input display as shown by the figure here. Entering data in the table is done by first selecting the desired table entry. You select a table entry by clicking the desired entry. If the table is empty, select the area in the first row. This is illustrated in the figure shown here. If the table contains Step Value information and you want to add another value, use the scroll bar, if necessary, to move to the end of the table and select the first empty area.


OPTIONS

Once a table entry is selected, the background of that entry will change to red and the cursor will be placed in the Edit Value Input Box. If the entry contains data, the data will be displayed in the Edit Value Input Box. You may then enter or change the step value in the Edit Value Input Box. You may enter up to 100 different step values. When you are satisfied with the new data, press ENTER. This will place the value in the highlighted table entry and move the cursor to the next available table entry. If TFREQ has a value greater than one, the step numbers given must be a multiple of TFREQ. Otherwise, they are ignored. When all the desired time steps have been entered, click on EXECUTE. This will save your selections and create the file. You will see the same message window that appeared for the INTERVAL option. You may close this display without specifying or changing any time step values by clicking the CANCEL push button. SELECT STEPS SELECT STEPS provides the capability to select time levels from the results file. When you click on the SELECT STEPS push button in the sub-menu, PostCAST displays the input display as shown the figure here. It will contain a list of the time levels in the results file. You select the steps to be output to the ASCII file by clicking on the desired table entries. As you select entries in this list, they will be highlighted with a red background. You may deselect an entry by clicking on it again with the left mouse button. Use the scroll bar, if necessary, to move to the desired table entry.

PAGE 6 - 20


OPTIONS

You may deselect every entry in the list by clicking the CLEAR push button. When all the desired time steps have been selected, click on EXECUTE. This will save your selections and create the file. You will see the same message window that appeared for the INTERVAL option. You may close this display without specifying or changing any time step values by clicking the CANCEL push button. Remarks

The ASCII file created by this function may be used as input for other analyses or reporting purposes outside of ProCAST.

Related Topics


OPTIONS

OPTIONS PRESSURE Description

PRESSURE is a push button in the OPTIONS menu. It provides the capability to extract pressure results from the prefixp.unf file, which is a binary file, and write them to an ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.

Method

PRESSURE is activated by clicking on it. This results in the immediate action to display a sub-menu of push buttons which are the methods you may use to designate the time step levels to be included in the output file. The figure shown here illustrates this sub-menu. The options available in this submenu work in the same way as the OPTIONS--TEMPERATURE menu item. Please see the OPTIONS--TEMPERATURE section of this manual for a description of these menu options, their syntax, and usage.

Remarks


Related Topics

OPTIONS--TEMPERATURE

PAGE 6 - 22


OPTIONS

OPTIONS VELOCITY Description

VELOCITY is a push button in the OPTIONS menu. It provides the capability to extract velocity results from the prefix(u, v, and w).unf files, which are binary files, and write them to an ASCII file. The three components of the velocity vector at each node are output for the selected time levels. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.

Method

VELOCITY is activated by clicking on it. This results in the immediate action to display a sub-menu of push buttons which are the methods you may use to designate the time step levels to be included in the output file. The figure shown here illustrates this sub-menu. The options available in this submenu work in the same way as the OPTIONS--TEMPERATURE menu item. Please see the OPTIONS--TEMPERATURE section of this manual for a description of these menu options, their syntax, and usage.

Remarks


Related Topics



OPTIONS

OPTIONS HEAT FLUX Description

HEAT FLUX is a push button in the OPTIONS menu. It provides the capability to extract heat flux results from the prefixq.unf file, which is a binary file, and write them to an ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.

Method

HEAT FLUX is activated by clicking on it. This results in the immediate action to display a sub-menu of push buttons which are the methods you may use to designate the time step levels to be included in the output file. The figure shown here illustrates this sub-menu. The options available in this submenu work in the same way as the OPTIONS--TEMPERATURE menu item. Please see the OPTIONS--TEMPERATURE section of this manual for a description of these menu options, their syntax, and usage.

Remarks


Related Topics


PAGE 6 - 24


OPTIONS

OPTIONS R, G, L Description

R, G, L is a push button in the OPTIONS menu. It provides the capability to specify the method for calculating the solidification rate (R), the method for calculating the temperature gradient (G), the upper and lower temperature levels to be used in calculating the cooling rate (L), and the constants to be used in calculating the mapping factor.

Method

R, G, L is activated by clicking on it. This results in the immediate action to display an input dialog box. The figure shown here illustrates this input dialog box.

Each of the parameters and options in this dialog box will be discussed in this section. You may close this display by clicking the CANCEL push button. R METHOD This push button is a toggle switch. Successive clicks on this push button will toggle between method 1 and 2. In Method 1, when each node reaches the specified temperature, a point is located along the temperature gradient some distance away and the time that it takes for the isotherm to reach that point is determined. R is then calculated as that distance divided by the difference in time. In Method 2, R is calculated as the cooling rate divided by the temperature gradient. Method 1 takes longer to compute, but it does not depend on the cooling rate. The results obtained by Method 2 are affected by the temperature levels used to calculate L.


OPTIONS

R METHOD options are: {1 | 2}. The default is 1. G METHOD This push button is a rotary toggle switch. Successive clicks on this push button will cycle through the available options. G METHOD determines if the total magnitude of the temperature gradient or one component used in the calculation of the mapping factor. G METHOD options are: {TOTAL | dT/dx | dT/dy | dT/dz}. The default is TOTAL. Normally, one would choose TOTAL, in which case, the following equation describes the magnitude of the temperature gradient.

G

0T 0x

0T 0y

2

2

0T 0z

2

1 2

L UPPER TEMP and L LOWER TEMP These input lines specify the temperature levels to be used in the calculation of the cooling rate, L. The following equation describes the calculation of the cooling rate; where, T is temperature and t is time to reach that temperature.

L

Tupper Tlower

tupper tlower

For example, Tupper could be the liquidus and Tlower the solidus. To enter these temperatures, place the cursor in the appropriate input line and type the desired value. You may move to the next input field by moving the cursor or by pressing ENTER. R, G TEMP This input line specifies the temperature to be used for the calculation of the isotherm velocity and the temperature gradient. If R, G TEMP is set to the solidus, then R will be the solidification rate. However, R can be calculated as an isotherm velocity for any temperature. The gradient, G, is computed at a given node when it reaches the R, G TEMP level. Therefore, G is calculated at a different time for each node. To enter this temperature, place the cursor in the R, G TEMP input line and type the desired value. You may move to the next input field by moving the cursor or by pressing ENTER. PAGE 6 - 26


OPTIONS

MAPPING CONSTANTS These input lines specify the constants to be used in calculating the mapping factor. The mapping factor is calculated from the formula shown here.

M aRbG cLd The a, b, c, and d are the user specified constants and correspond to the MAPPING CONSTANTS input lines. The default values for these constants yield the Niyama criterion,

M

G L

In the literature, L is often expressed as T . If the constant is a given the value of zero, the mapping factor will not be computed. You may click on the HELP push button to obtain more information about various combinations of the constants which produce different mapping factors. When all the desired values have been entered, click on APPLY. This will save your selections and create the mapping factors and mapping factors log files. A message window will be displayed indicating when the files have been successfully completed. You may close this display without specifying or changing any values by clicking the CANCEL push button. Remarks

R, G, L stands for solidification rate (R), temperature gradient (G), and cooling rate (L). R is the velocity of a particular isotherm. G is the gradient calculated at each node when that node reaches a given temperature. L is the time derivative of temperature, calculated as the difference of two temperature levels divided by the difference in time at which those temperatures are reached. Choosing the R, G, L option will produce all of these results. In addition, they can be combined into a single product, called a mapping factor, which can be a useful indicator of many metallurgical features. The Niyama criteria for porosity is an example. The mapping factor log contains the temperature levels and the constant values that were used in calculating R, G, L, and M. By default, only a binary output file is produced for ViewCAST. If you select PATRAN or IDEAS under the FORMAT menu, an ASCII file with the extension "ntl" will also be created. This neutral file contains ten


OPTIONS

columns or sets of data as detailed below:

Related Topics

PAGE 6 - 28


Column/Set

Quantity

1

M

2

L

3

G

4

dT/dx

5

dT/dy

6

dT/dz

7

R

8

Rx

9

Ry

10

Rz

OPTIONS

OPTIONS FEEDING LENGTH Description

FEEDING LENGTH is a push button in the OPTIONS menu. It provides the capability to calculate the distance between the solidus and some user defined critical temperature which represents some fraction solid beyond which feeding is impaired. This distance is then compared with a “critical feeding length,” which is a simple linear function of the hydrostatic pressure. If the feeding distance exceeds the critical length, then porosity would be likely.

Method

FEEDING LENGTH is activated by clicking on it. This results in the immediate action to display an input dialog box. The figure shown here illustrates this input dialog box.

Each of the parameters and options in this dialog box will be discussed in this section. You may close this display by clicking the CANCEL push button. A and B These input lines allow the user to enter the constants for the critical feeding length equation. These critical temperatures represent some fraction solid beyond which feeding is impaired. To enter these temperatures, place the cursor in the appropriate input line and type the desired value. You may move to the next input field by moving the cursor or by pressing ENTER.


OPTIONS

SOLIDUS This input line is for the solidus temperature of the metal. To enter this temperature, place the cursor in the appropriate input line and type the desired value. You may move to the next input field by moving the cursor or by pressing ENTER. CRITICAL This input line is for a temperature value which corresponds to a fraction solid greater than zero and less than one. The critical fraction solid at which feeding is impaired depends on the alloy, but is typically in the range of .6 to .8. To enter this value, place the cursor in the appropriate input line and type the desired value. You may move to the next input field by moving the cursor or by pressing ENTER. When all the desired values have been entered, click on APPLY. This will save your selections and close the display. Remarks

The critical feeding length is calculated from the formula shown here.

F Lcr A P B

P is the hydrostatic pressure head. P is calculated automatically from the geometry of the casting and the metal density. Related Topics

PAGE 6 - 30


OPTIONS

OPTIONS ISOCHRONS Description

ISOCHRONS is a push button in the OPTIONS menu. It provides the capability to produce contours of the time that it takes to reach specified temperature levels.

Method

ISOCHRONS is activated by clicking on it. This results in the immediate action to display a submenu which contains two optional methods for specifying the temperature levels to be used. The figure shown here illustrates this submenu. When you select either option, by clicking on the desired push button, an input dialog box will be displayed. Each option in this sub-menu will be discussed in this section. You may close this display and move to another function of PostCAST or to another function of OPTIONS by clicking the appropriate Main Function Banner or Menu push button respectively. SEMI-AUTO Provides the capability to generate the temperature levels based upon your input of two parameters. When you activate the SEMIAUTO push button an input dialog box is displayed. This is illustrated in the figure here. Twenty temperature levels will be generated using the START value and incremented by the DELTA value. START--enter the starting temperature level to be used. Place the cursor in the appropriate input line, type the desired value, and press ENTER. DELTA--enter the amount of temperature change you want between the generated temperature levels. Place the cursor in the appropriate input line, type the desired value, and press ENTER.


OPTIONS

Click on the APPLY push button when you are satisfied with the START and DELTA values. You may close this display by clicking the CANCEL push button.

SPECIFY TEMPS SPECIFY TEMPS provides the capability to directly input the desired temperature levels. When you click on the SPECIFY TEMPS push button in the sub-menu, PostCAST displays the input display as shown the figure here. Entering data in the table is done by first selecting the desired table entry. You select a table entry by clicking on the desired entry. If the table is empty, select the area in the first row. This is illustrated in the figure shown here. If the table contains temperature information and you want to add another value, use the scroll bar, if necessary, to move to the end of the table and select the first empty area. Once a table entry is selected the background of that entry will change to red and the cursor will be placed in the Edit Value Input Box. If the entry contains data, the data will be displayed in the Edit Value Input Box. You may then enter or change the step value in the Edit Value Input Box. You may enter up to 50 different temperature levels in this table. When you are satisfied with the new data, press ENTER. This will place the value in the highlighted table entry and move the cursor to the next available table entry. When you are satisfied with the temperature levels in this table, click on the EXECUTE push button. This will close this display, calculate the temperature levels, and build the file.

PAGE 6 - 32


OPTIONS

With either the SEMI-AUTO or SPECIFY TEMPS method, clicking on APPLY or EXECUTE will save your input and create the isochrons and temperature level log files, respectively. A message window will be displayed indicating when the files have been successfully completed. Remarks

ISOCHRONS are particularly useful for identifying hot spots and necking. By default, only a binary output file is produced for ViewCAST. If you select PATRAN or IDEAS under the FORMAT menu, an ASCII file with the extension "ntl" will also be created.

Related Topics


OPTIONS

OPTIONS ALPHA CASE Description

ALPHA CASE is a push button in the OPTIONS menu. It creates an ASCII file containing information about the thickness of alpha case for the surface nodes adjacent to the ceramic shell in Titanium alloy investment castings.

Method

ALPHA CASE is activated by clicking on it. This results in the immediate action to build the output file. This file can also be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.


The ALPHA CASE option is only used in Titanium castings. In Titanium castings there is a very brittle alpha ( ) layer that forms on the casting. The ALPHA CASE is used to predict the thickness of this layer. Surface regions of Ti alloy investment castings are usually contaminated with oxygen due to reactivity of the metal with the ceramic shell mold during solidification and subsequent cooling from elevated temperatures. The local increase of O2 content at the surface promotes the formation of oxygen-rich Ti hexagonal solid solution ( phase) at temperatures when bulk alloy is single phase beta ( ). This also alters the alpha/beta structure near the surface during cooling to room temperature.

PAGE 6 - 34


OPTIONS

Usually the thickness of this brittle layer ranges from 50 to 2000 microns. This leads to deterioration of surface mechanical properties and it must be removed by chemical milling before use. The thickness of the layer needs to be predicted to determine milling time and to determine excess thickness to be factored into the design of as-cast dimensions. The model assumes a few typical numbers for O2 concentration at the surface, bulk region, and at the edge of the alpha case region. Also, standard values are obtained for the diffusion coefficient and activation energy from the literature. The ALPHA CASE option is only used in Titanium castings. In Titanium castings there is a very brittle oxide layer that forms on the casting. The ALPHA CASE is used to predict the thickness of the oxide layer. Related Topics


OPTIONS

OPTIONS SDAS Description

SDAS is a push button in the OPTIONS menu. It provides the capability of calculating the Secondary Dendrite Arm Spacing (SDAS) based upon the thermal history.

Method

SDAS is activated by clicking on it. This results in the immediate action to display an input dialog box. The figure shown here illustrates this dialog box. Each parameter in this dialog box will be discussed in this section. You may close this display and move to another function of PostCAST or to another function of OPTIONS by clicking the appropriate Main Function Banner or Menu push button respectively. SDAS is calculated according to the following: SDAS = ( M * (tend - tstart))exp Where: tend = time to reach Tend tstart = time to reach Tstart TSTART Normally taken as the liquidus. Enter the temperature value to be used by placing the cursor in the appropriate input line, typing the desired value, and pressing ENTER. TEND Normally the eutectic temperature. Enter the temperature value to be used by placing the cursor in the appropriate input line, typing the desired value, and pressing ENTER.

PAGE 6 - 36


OPTIONS

EXPONENT Provides the capability to enter the exponent to be used in the formula shown above. Enter the exponent by placing the cursor in the appropriate input line, typing the desired value, and pressing ENTER. M Provides the capability to specify the coarsening constant and is alloy dependent. Enter the coarsening constant to be used by placing the cursor in the appropriate input line, typing the desired value, and pressing ENTER. When you are satisfied with the values you have entered, click on the APPLY push button. This will close this display, extract the appropriate data, and build the ASCII file. A message window will be displayed indicating when the files have been successfully built. Remarks

In practice there is a correlation between the SDAS and mechanical properties. The finer the spacing of the SDAS, the greater the strength. The figure here, illustrates what SDAS is.

Related Topics


OPTIONS

OPTIONS ROW SUM ERROR Description

ROW SUM ERROR is a push button in the OPTIONS menu. It creates an ASCII file containing the nodal values of row sum errors, if a simulation used the view factor radiation capabilities. These are averaged from the row sum errors on the faces surrounding each node. Only the nodes on the radiating surfaces will have non-zero values.

Method

ROW SUM ERROR is activated by clicking on it. This results in the immediate action to build the ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.


PostCAST looks for a file produced by ProCAST with the name prefix.serr. This file is output from ProCAST if the value of one has been added to RDEBUG in the prefixp.dat file.

Related Topics

PAGE 6 - 38


OPTIONS

OPTIONS FACE TO GROUP Description

FACE TO GROUP is a push button in the OPTIONS menu. It creates an ASCII file containing the nodal values of aggregate view factors. This option is only available if a simulation used the view factor radiation capabilities. It is not necessary to create this ASCII file if you are using ViewCAST for graphical postprocessing.

Method

FACE TO GROUP is activated by clicking on it. This results in the immediate action to build the ASCII file. This file can be written in either the PATRAN neutral file or the IDEAS universal file format, depending upon the format selected from the FORMAT function in the Main Function Banner of PostCAST.


A “face to group view factor” is the fraction of the view space from a face that is occupied by one group. A group is an assembly of enclosure or solid faces that have the same boundary condition. The nodal values are averaged from the surrounding face values. Only the nodes on the radiating surfaces will have non-zero values. PostCAST will look for a file produced by ProCAST with the name prefix.view. This file is output from ProCAST if the value of two has been added to RDEBUG in the prefixp.dat file.

Related Topics


FORMAT

FORMAT Description

FORMAT is a push button in the Main Function Banner. This function of PostCAST enables you to specify the type of ASCII results files to be produced. When you activate the FORMAT push button, a menu is opened which will allow you to choose the specific output file format to be used.

Method

FORMAT is activated by clicking on it. The resulting menu is shown here. You select either the PATRAN neutral file format or the IDEAS universal file format by clicking on the check box to the left of either label in the menu. When you select a format, the background of the respective check box will be highlighted in red. These check boxes may be toggled between on and off by successively clicking the check box. Additionally, these check boxes are mutually exclusive. You may leave the FORMAT function by clicking another push button in the Main Function Banner. If you are using ViewCAST for graphical postprocessing, it is not necessary to choose either PATRAN or IDEAS to see the results.

Remarks

You do need to pick one or the other for the GEOMETRY and RADIATION FACE options. Related Topics

PAGE 6 - 40


OPTIONS--RADIATION FACE, OPTIONS--GEOMETRY

STEPS

STEPS Description

STEPS is a push button in the Main Function Banner. This function enables you to control the time steps used in various operations of PostCAST. When you activate the STEPS push button, a menu is opened which will allow you to enter time step parameters. Each of these parameters available from this menu will be discussed in this section.

Method

STEPS is activated by clicking on it. The resulting menu input dialog box is shown here. You select the parameter by clicking the desired parameter. When a parameter is selected, its background will be highlighted in red. You may leave the STEPS function by clicking another push button in the Main Function Banner. START Specifies the beginning time step. Enter the beginning time step by selecting START, placing the cursor in the Edit Value input line, typing the desired value, and pressing ENTER. END Specifies the ending time step. Enter the ending time step by selecting END, placing the cursor in the Edit Value input line, typing the desired value, and pressing ENTER. FREQUENCY Specifies the frequency of the time steps to be used between the START and END values. Enter the frequency by selecting FREQUENCY, placing the cursor in the Edit Value input line, typing the desired value, and pressing ENTER.

Remarks

The parameters given under STEPS determine which time levels are used when plotting the temperature-time curves. They control the time levels for which results are output in the ASCII files for temperature, pressure, velocity, and heat flux. The calculations performed for R, G, L, FEEDING LENGTH, and ISOCHRONS are all based upon the temperature results available at the time levels chosen under STEPS.


STEPS

You can speed up these computations by using a FREQUENCY greater than one because not as many data points have to be examined. However, the accuracy of the results may be diminished by using too large a value for FREQUENCY. The values for START, END, and FREQUENCY should be multiples of VFREQ for pressure and velocity, and multiples of QFREQ fro heat flux. For all other cases, they should be multiples of TFREQ. The beginning and ending time steps, and the frequency that are specified here are used in the following functions: 1. X---Y PLOT, TEMPERATURE, INTERVAL option 2. X---Y PLOT, FRACTION SOLID, INTERVAL option 3. X---Y PLOT, PRESSURE, INTERVAL option 4. X---Y PLOT, VELOCITY, INTERVAL option 5. TEMPERATURE, INTERVAL option 6. PRESSURE, INTERVAL option 7. VELOCITY, INTERVAL option 8. HEAT FLUX, INTERVAL option 9. R, G, L 10. FEEDING LENGTH 11. ISOCHRONS Related Topics

PAGE 6 - 42


UNITS

UNITS Description

UNITS is a push button in the Main Function Banner. This function of PostCAST enables you to specify the units of measure to be used in the ASCII output files.

Method

UNITS is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the unit of measure types. Next to each category of units is a rotary toggle switch which will display the available options for each of the categories. Successive clicks on these toggle switches will cycle through the available options. The figure shown here illustrates the UNITS dialog box. The UNITS parameters and the available options for each parameter will be presented here. For convenience in presentation, they will be presented in alphabetical order. HEAT FLUX--specifies the heat flux units to be used in the outputs. Choose from: { W/m**2 | cal/cm**2/sec | cal/mm**2/sec | Btu/ft**2/sec | Btu/in**2/sec | cal/cm**2/min | cal/mm**2/min | Btu/ft**2/min | Btu/in**2/min} The default is specified in QUNITS in the prefixp.dat file. LENGTH--specifies the length units to be used in the outputs. Choose from: {m | cm | mm | ft | in} The default is centimeters. PRESSURE--specifies the pressure units to be used in the outputs. Choose from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} The default is specified in PUNITS in the prefixp.dat file.


UNITS

TEMPERATURE--specifies the temperature units to be used in the outputs. Choose from: {C | F | R | K} The default is specified in TUNITS in the prefixp.dat file. VELOCITY--specifies the velocity units to be used in the outputs. Choose from: {m/sec | cm/sec | mm/sec | ft/sec | in /sec | m/min | cm/min | mm/min | ft/min | in/min} The default is specified in VUNITS in the prefixp.dat file. You may close this display and move to another function of PostCAST by clicking the appropriate Main Function Banner. Remarks

The length units are used in the temperature gradient and feeding length calculations. The temperature units are used in the TEMP-TIME PLOTS, TEMPERATURE, R, G, L, FEEDING LENGTH, and ISOCHRON functions. Heat Flux, Pressure, and Velocity units affect their respective output in the ASCII results files.

Related Topics

PAGE 6 - 44


RUN PARAMETERS--UNITS

MATERIALS


MATERIALS is a push button in the Main Function Banner. This function of PostCAST enables you to specify the material regions of the model that are to be active in the calculations of the [R, G, L], FEEDING LENGTH,SDAS, X-Y PLOTS, GEOMETRY, TEMPERATURE, and ISOCHRONS functions.

Method

MATERIALS is activated by clicking on it. This results in the immediate action to display a list of all the materials in the model. The figure shown here illustrates the MATERIALS list. All materials that are highlighted in red will be active in the calculations. Materials may be excluded from these calculations by clicking the left mouse button on the row associated with the material to be deactivated. You may deactivate all materials by clicking the ALL push button in the Materials List display. You may reactivate a material by clicking on the material’s entry in the list. You may close this display and move to another function of PostCAST by clicking the appropriate Main Function Banner. You may close this display without saving any settings you may have made by clicking the CANCEL push button.

Remarks

You can speed up the calculation process for your model by deactivating the materials for which the [R, G, L], FEEDING LENGTH,SDAS, X-Y PLOTS, GEOMETRY, TEMPERATURE, and ISOCHRONS results are not of interest. Usually, you can turn off everything but the casting material.

Related Topics


MATERIALS


PAGE 6 - 46


USING VIEW CAST

CHAPTER 7 USING ViewCAST Description

ViewCAST provides the capability to visualize the results of the simulation. ViewCAST performs rapid contour plots of all results based upon time step intervals which you may specify. For example, temperature contours can be plotted at every time step automatically, giving an animated effect. Also a cutting plane option allows you to see inside the casting. You may choose from extensive menus of contours and vectors for viewing.

Method

ViewCAST runs in a either a Unix or a Microsoft Windows NT session window. ViewCAST can be started using the following command line instruction at the session window prompt or the Run Dialog Window: viewcast {prefix} [ -m, -G ] ENTER Prefix is a required parameter and you should enter the name you want given to this project. ViewCAST may also be started from the EXECUTE menu in the PCS screen. The -m optional parameter is a switch for memory usage. The -G optional parameter is a switch for graphics statistics.

Remarks

If you start a ViewCAST session without the prefix parameter shown above, you will be given an error message in the session window and prompted to enter a prefix. Operational procedures and standards at your installation may specify additional start-up requirements such as passwords, working directory specifications, and project or file naming conventions. Consult your installation or network manager for these guidelines. The general procedure for viewing a contour or a vector is as follows: 1. Run PostCAST to extract/calculate the desired data. For some contours, you must use PostCAST to process the simulation results in order to extract the data of interest to you. For example, in ViewCAST you can display an ISOCHRON contour which shows the time required to reach a given temperature. Running PostCAST is only necessary for a subset of all variables. These are: Isochrons, Mapping Factors, Cooling Rates, Isotherm Velocity, Temperature Gradients, Alpha Case, SDAS, and Feeding Length. 2. Set the desired Steps, Parameters, and Materials for viewing. ViewCAST enables you to tailor the visualization of results to USING VIEW CAST, PAGE 7 - 1

USING VIEW CAST

best suite your analysis requirements. You can use the Steps function to display a specific time step or a selected range of time steps. The Materials function allows you to choose, based upon material region, the results to be displayed. The Parameters function allows you to refine the presentation of the data during viewing. For example, you may adjust the units of measure, color legend, background color, and whether the visualization will be presented in a continuous or single step mode. 3. Activate the view. This function of ViewCAST displays the results. The graphic display window will be redrawn to show the material regions corresponding to your selection. Additionally, during Single Step, a set of up to four push buttons will be displayed in the lower right corner of the graphics display. These push buttons allow you to; STore a copy of the image in a file or Print a copy of the image. While the right arrow and left arrow allow you to step forward and backward, respectively through the results. These buttons are shown here along with the dialog box which is displayed when you select the STore option. This dialog box allows you to name the file to be created when storing the image. The number of buttons shown is determined by ViewCAST based upon the context and the specific results in which you

are working. For example, if you are displaying Isochrons, ViewCAST will display the first plot corresponding to the first temperature you specified. It will also display all four push buttons. This will allow you to step through all of the Isochrons generated in PostCAST. If you are viewing the results in the Continuous Mode and click on PAUSE, The STore and Print buttons will be displayed. When ViewCAST is activated, it will display a work space, the UES logo in the lower right-hand corner, and a Main Function Banner across the top of the work space. You may use the push buttons in this banner to navigate through the function menus of ViewCAST.

PAGE 7 - 2


USING VIEW CAST

These Function Banner buttons are: CONTOUR, VECTOR, STEPS, PARAMETERS, MATERIALS, VIEW, PAUSE, and EXIT Each of these functions are described in the following pages. They are presented in the order shown above which corresponds to their left-toright placement in the Function Banner. This also approximates the order in which you would ordinarily use the functions of ViewCAST. Related Topics

CONTOUR, VECTOR, STEPS, PARAMETERS, MATERIALS, VIEW, PAUSE, EXIT

USING VIEW CAST, PAGE 7 - 3

CONTOUR

CONTOUR Description

CONTOUR is a push button in the Main Function Banner. This function of ViewCAST enables you to select the category of analysis results to be viewed. The CONTOUR push button displays a menu. The options in this menu represent categories of simulation results. The functions available from this menu will be discussed in this section.

Method

CONTOUR is activated by clicking on it. The initial menu is shown here. When you select a function from this menu, ViewCAST displays submenus which itemize the optional classes of contours which are available. This menu and the subsequently displayed sub-menus are lists of mutually exclusive contour options. Only one contour option can be active at a time. After the first selection has been made, subsequent selections will cancel the previously chosen contour option. When you select a contour from a menu, it will be highlighted with a blue background and the menu and sub-menu will be closed. To display the contour, click on the VIEW push button in the main function banner and then click on PICTURE. You may deactivate all contours by clicking the NONE menu option. You may leave the CONTOUR function by clicking another push button in the Main Function Banner. Each Contour Group will be discussed in the Remarks Section immediately below.

Remarks

PAGE 7 - 4

The CONTOUR function of ViewCAST provides the capability to view the results of the ProCAST simulation from perspectives which will support your specific analytical requirements. For convenience, these views have been grouped as shown in the menu list above. Each of these groups will be discussed here.


CONTOUR

THERMAL Contours The figure shown here illustrates the THERMAL sub-menu and displays the temperature-related views which are available. TEMPERATURE, FRACTION SOLID, HEAT FLUX, and SOLIDIFICATION TIME contours will be available if a thermal analysis has been run with ProCAST. ISOCHRONS, MAPPING FACTORS, COOLING RATES, TEMPERATURE GRADIENTS, ISOTHERM VELOCITY, FEEDING LENGTH, ALPHA CASE, and SDAS data is calculated by PostCAST from temperature results. Setting the POROS parameter in the Thermal Run Parameters to a value of 1 will make the MACRO POROSITY data available, and setting the POROS parameter to a value of 2 will make the GAS POROSITY and the BUBBLE RADIUS results available. Temperature--displays the temperatures present, at specific time steps, in the model. A temperature contour is illustrated below.


CONTOUR

Fraction Solid--displays a representation of the amount of solidification which has taken place in the model at specific time steps. A fraction solid contour is illustrated here.

Heat Flux--displays a representation of the rate of heat flow, per unit area. Isochrons--display a plot of the time taken to get to a specified temperature. The Isochrons which are available for viewing depend upon the selection you make in the OPTIONS–ISOCHRONS function of PostCAST. The example shown here illustrates the elapsed time, in various portions of the casting, to reach 1070(C.

Mapping Factors--plots the results of the quantity calculated from the combination of R, G, and L and is generally used as a porosity indicator.

PAGE 7 - 6


CONTOUR

Cooling Rates--displays the cooling rates in degrees per unit of time between the temperatures specified in the R, G, L options of PostCAST. In this example, the cooling rates were calculated between the pour temperature of 1385 and 1000(C.

Temperature Gradients--displays the magnitude and direction of the spatial change of temperature. The gradient is composed of the x, y, and z components. The example shown here, illustrates the four views which ViewCAST provides. In practice

these temperature gradients can identify the degree of temperature variation in the model.


CONTOUR

Isotherm Velocity--plots the results of the solidification rate (R) or velocity of the isotherm value specified in the R, G, L, Option of PostCAST. Feeding Length--displays a plot of the distances between the solidus and a user defined temperature that represents some fraction solid beyond which feeding is impaired. This is a porosity indicator. Solidification Time--displays a plot of the time from the beginning to the end of solidification. In the example shown here, the solidification time is illustrated with a cross section of the casting.

Macro Porosity--displays the results of the macro porosity calculations. Gas Porosity--displays the results of the porosity effects associated with a dissolved gas. Bubble Radius--displays a plot of the bubble radius as a result of the gas porosity calculations. Alpha Case--displays the results of the calculation of Titanium oxide formation. Secondary Dendrite Arm Spacing (SDAS)--plots the results of an SDAS analysis.

PAGE 7 - 8


CONTOUR

FLUID Contours The figure shown here illustrates the FLUID sub-menu and displays the fluid-related views which are available. The U, V, W are the velocity components in the X, Y, and Z directions respectively. PRESSURE and VELOCITY contours will be available if a fluid flow analysis has been run with ProCAST. If the fluids analysis has been run with the --- turbulence model turned on, the TURBULENT ENERGY, TURBULENT DISSIPATION, and TURBULENT VISCOSITY contours will be available. If the fluids analysis has been run with the NNEWTON parameter set to 1 or 2, the NON-NEWTONIAN SHEAR RATE and VISCOSITY contours will be available. RADIATION Contours The figure shown here illustrates the RADIATION sub-menu and displays the radiation-related views which are available. Row Sum Errors–displays a contour of the nodal values of the row sum errors. These errors are caused by gaps in the casting or enclosure. Face To Group View Factors–displays the nodal values of aggregate view factors. A group is an assembly of enclosure or solid faces that have the same boundary condition. The nodal values are averaged from the surrounding face values. These contours are available if a radiation analysis was run with view factors specified. The RDEBUG parameter in the prefixp.dat file should have the values of 1 and 2 added to it in order to cause ProCAST to produce the files prefix.serr and prefix.view.


CONTOUR

STRESS Contours The figure shown here illustrates the STRESS sub-menu and displays the stress-related views which are available. The state of stress at a point can be characterized by three normal components, )x , )y, )z, and three shear components, )xy, )yz, )xy. )xy is the shear stress in the x direction on the y plane and so on. It is possible to find three planes going through this same point on which the shear stress is zero and there is only a normal stress. These are called the principal stresses, )1, )2, )3, ranked in descending order of magnitude. These are the roots of the following cubic equation:

σ 3 − ( σ x + σ y + σ z ) σ 2 + ( σ x σ y + σ y σ z + σ x σ z − σ xy2 − σ yz2 − σ xz2 ) σ − ( σ x σ y σ z + 2 σ xy σ yz σ xz − σ x σ yz2 − σ y σ xz2 − σ z σ xy2 ) = 0 Effective Stress–is an invariant combination of the principal stresses that gives a single value representation of the state of stress, rather than a tensor. This value is used for checking the condition for yielding, i.e., plastic deformation. It is equivalent to the Von Mises stress, given by the formula:

σ m ax =

σ1 − σ 3 2

Maximum Shear Stress–is also used sometimes as a criteria for yielding. It is given by the formula:

σ =

[

2 (σ 1 − σ 2 ) 2 + (σ 2 − σ 3 ) 2 + (σ 3 − σ 1 ) 2 2

]

1/ 2

Average Normal Stress–is also known as the hydrostatic or mean stress. It is given by the formula:

σm =

σ1 + σ 2 + σ 3 σ x + σ y + σ z = 3 3

Principal Stress 1--stress resolved to the direction the highest magnitude of stress. Principal Stress 2–stress resolved to the direction perpendicular to Stress 1. Principal Stress 3–stress resolved into or out of the plane described by Stresses 1 and 2. Sigma X--stress resolved to the x direction. PAGE 7 - 10


CONTOUR

Sigma Y--stress resolved to the y direction. Sigma Z–stress resolved to the z direction. Sigma XY--shear stress in the x-y plane. Sigma YZ--shear stress in the y-z plane. Sigma ZX--shear stress in the z-x plane. Effective Plastic Strain--displays a representation of normalized strain after it goes plastic. Strain--the change in relative positions of points in a medium as the result of stress-produced deformation. X Displacement--the amount of deformation in the x direction. Y Displacement--the amount of deformation in the y direction. Z Displacement--the amount of deformation in the z direction. MICRO contours A MICRO sub-menu displays the micro model-related views which are available. The actual sub-menu which will be displayed will depend upon the type of analysis that has been performed. The outputs from all the different micromodels are described in the Appendix. ELECTROMAGNETICS Contours The figure shown here illustrates the ELECTROMAGNETICS sub-menu and displays the electromagnetic-related views which are available. A = magnetic vector potential. This is a complex number, with real and imaginary components. This sub-menu allows you to provide each of the components of A. They include: Real Ax, Imaginary Ax, Real Ay, Imaginary Ay, Real Az, Imaginary Az, and Magnitude A. Induction Heating--is the heat generated by induced current. Eddy Current--is the electric current induced by magnetic field. Real B--magnetic flux density. Imaginary B--magnetic flux density. Lorentz Force--plots the force on a fluid due to the presence of an electric current and magnetic field. Related Topics

Maxwell’s equations in APPENDIX C


VECTOR

VECTOR Description

VECTOR is a push button in the Main Function Banner. This function of ViewCAST enables you to select a vector plot of selected analysis results. The VECTOR push button displays a menu of choices for producing vector plots. The functions available from this menu will be discussed in this section.

Method

VECTOR is activated by clicking on it. The resulting menu is shown here. The options in this menu are mutually exclusive. Only one vector plot option can be active at a time. After the first selection has been made, subsequent selections will cancel the previously chosen option. When you select a vector option from the menu, it will be highlighted with a blue background and the menu will be closed. It is possible to have vector plots superimposed on contour plots. For example, fluid velocity vectors displayed on top of temperature contours can provide a great deal of information in viewing filling transient results. To superimpose a vector plot on a contour plot, select the desired contour by clicking on it in the CONTOUR menu and then select the desired vector from the VECTOR menu. The example below illustrates how the Fluid Velocity Vector plot is superimposed on the Fluid Velocity–Magnitude Contour. To display the plot, click on the VIEW push button in the main function

banner and then click on PICTURE. You may deactivate all vectors by clicking the NONE menu option. You may leave the VECTOR function by clicking another push button in the Main Function Banner. Each menu option will be discussed in the Remarks Section immediately below. Remarks PAGE 7 - 12

The VECTOR function of ViewCAST provides the capability to view the PROCAST USER’S MANUAL

VECTOR

magnitude and orientation for selected results from a ProCAST simulation. FLUID VELOCITY--Fluid Velocity vectors will be available if a flow analysis has been run with ProCAST. This plot displays the magnitude and direction of the fluid flow at specific time steps. The illustrations shown here demonstrate the capability to zoom

in on portions of the model and examine the plot at different time steps. The TEMPERATURE GRADIENTS and ISOTHERM VELOCITY options require that the R, G, L function be executed using PostCAST to extract these vector quantities from the thermal results.


VECTOR

TEMPERATURE GRADIENTS–displays the magnitude and direction of the temperature change. In the example shown here, the

temperature gradient is plotted based upon the temperature of 1153(C which was specified in the R, G, L Options of PostCAST. ISOTHERM VELOCITY---plots the vector results of the solidification rate (R) or velocity of the isotherm value specified in the R, G, L, Option of PostCAST. In the example shown here, the isotherm velocity is plotted based upon the temperature of 1153(C.

PAGE 7 - 14


VECTOR

HEAT FLUX–displays the heat transfer into or out of the model. This vector plot is illustrated here. REAL B FIELD–displays the magnetic flux density. Electromagnetic

flux is described by a complex number. This vector plots the flux associated with the real component of that number. IMAGINARY B FIELD–displays the magnetic flux density. Electromagnetic flux is described by a complex number. This vector plots the flux associated with the imaginary component of that number. Lorentz Force–plots the force on a fluid due to the presence of an electric current and magnetic field. Related Topics


STEPS

STEPS Description

STEPS is a push button in the Main Function Banner. This function of ViewCAST enables you to control which time levels are used in the sequence of contour plots of temperature, pressure, velocity, and heat flux. These time steps will also be applied to fluid velocity vector plots. The STEPS push button displays an input dialog box.

Method

STEPS is activated by clicking on it. The list and dialog input box, shown here, will be displayed. To enter a value for any of the three options, select the option by clicking on the desired entry in the list. The background of the selected entry will be highlighted in red. Then insert the cursor in the text input line, type the desired value, and press ENTER. The value you typed will be displayed in the respective entry in the list and the background of the next entry in the list will be highlighted in red. You may enter or change any value in the list by repeating the selecttype-ENTER procedure described above. The entries in this list define the following: START--specifies the first time step to be displayed for viewing. END--specifies the last time step to be displayed for viewing. FREQUENCY--specifies the number of steps between successive displays. You may leave the STEPS function by clicking another push button in the Main Function Banner. Depending upon the options you selected in the CONTOUR and VECTOR menus, the values given for START, END, and FREQUECY should be multiples of TFREQ, VFREQ, SFREQ, MFREQ, or QFREQ.

Remarks

Related Topics

PAGE 7 - 16


MATERIALS


MATERIALS is a push button in the Main Function Banner. This function of ViewCAST enables you to specify the material regions of the model which are to be displayed in the graphics area.

Method

MATERIALS is activated by clicking on it. This results in the immediate action to display a list of all the materials in the model. The figure shown here illustrates the MATERIALS list. Initially, all materials will be highlighted with a red background and will be displayed. Materials may be excluded from these calculations by clicking the left mouse button on the row associated with the material to be deactivated. You may deactivate all materials by clicking the ALL push button in the Materials List display. You may reactivate a material by clicking on the material’s entry in the list. You may close this display and move to another function of ViewCAST by clicking the appropriate Main Function Banner or by clicking the QUIT push button.

Remarks

As an example of how you may use this feature, consider removing the mold elements from the display. This would allow you to view the casting by itself. Selections in this window do not alter the results or data files, they merely specify which mesh elements will be displayed in the graphics viewing area.

Related Topics

PARAMETERS USING VIEW CAST, PAGE 7 - 17

PARAMETERS

Description

PARAMETERS is a push button in the Main Function Banner. This function of ViewCAST enables you to manage the graphical output which will be displayed. The options in this menu allow you to control the color coding used to display contours and vectors, adjust the intensity and hue of the colors used, label the output displays, and display “complete” geometries which were modeled using rotational or mirror symmetry. The functions available from this menu will be discussed in this section.

Method

PARAMETERS is activated by clicking on it. The initial menu is shown here. When you select a function from this menu, ViewCAST displays additional Dialog Boxes, Option Lists, Data Input Windows, or sub-menus. These graphical interface tools will guide you through the process of specifying, changing or deleting information about the options and their alternative attributes. Some of these switches, such as REVERSE VIDEO, toggle between on and off. Some other toggle switches, such as ALL VECTORS, are rotary toggle switches and cycle through the available alternatives for display attributes. You may leave the PARAMETERS function by clicking another push button in the Main Function Banner. Each PARAMETERS menu item will be discussed immediately below. REVERSE VIDEO REVERSE VIDEO is a toggle switch which toggles between ON and OFF. In the ON position, the background color of the contour and vector plots will be displayed in white. In the OFF position, which is the default, the background will be displayed in black. This may be useful, at times, for hard copy output. The toggle button is highlighted in maroon to indicate the ON position.

PAGE 7 - 18


PARAMETERS

AUTOMATIC AUTOMATIC is a toggle switch which toggles between ON and OFF. In the ON position, which is the default, the color coding for displaying contours will be determined by dividing the entire range of values of the variable to be displayed into equal segments. Each of these calculated segments will be assigned to one of fifteen colors. The toggle button is highlighted in maroon to indicate the ON position. AUTOMATIC is toggled to the OFF position when you select and activate either the SEMI-AUTO or MANUAL options of the PARAMETERS menu. SEMI-AUTO SEMI-AUTO provides the capability for you to define the color coding to be used for displaying contours. ViewCAST will determine the range of values to be assigned to a color based upon the values you provide. When you select SEMI-AUTO, the list and dialog input box, shown here, will be displayed. To enter a value, select the list item by clicking on it. The background of the selected entry will be highlighted in red. Then insert the cursor in the text input line, type the desired value, and press ENTER. The value you typed will be displayed in the respective entry in the list and the background of the next entry in the list will be highlighted in red. You may enter or change any value in the list by repeating the selecttype-ENTER procedure described above. The entries in this list define the following: BASE--specifies the initial value of the attribute to be displayed upon which all display segments will be based. DELTA--specifies the size of the range of values to be included in each of the fifteen color segments. The delta may be either positive or negative, depending on whether you want the levels to go up or down from the base value. Each of these calculated segments will be assigned to one of fifteen colors. The toggle button is highlighted in maroon to indicate the ON position. You may turn off the SEMI-AUTO option by activating either the AUTOMATIC or MANUAL options of the PARAMETERS menu. You may leave the SEMI-AUTO option by clicking another push button in the Main Function Banner or by clicking the QUIT push button.


PARAMETERS

MANUAL MANUAL provides the capability for you to define the color coding to be used for displaying contours. When you use this option, you assign specific values to be associated with a color segment. When you select MANUAL, the list and dialog input box, shown here, will be displayed. To enter a value, select the list item by clicking on it. The background of the selected entry will be highlighted in red. Then insert the cursor in the text input line, type the desired value, and press ENTER. The value you typed will be displayed in the respective entry in the list and the background of the next entry in the list will be highlighted in red. You may enter or change any value in the list by repeating the select-type-ENTER procedure described above. Each of entered value will be assigned to a color for display purposes. The toggle button is highlighted in maroon to indicate the ON position. You may turn off the MANUAL option by activating either the AUTOMATIC or SEMI-AUTO options of the PARAMETERS menu. You may save these color assignments by clicking the STORE push button and entering a file name in the Input Dialog Box which will be displayed. You may leave the MANUAL option by clicking another push button in the Main Function Banner or by clicking the DONE push button.

PAGE 7 - 20


PARAMETERS

FREE SURFACE This toggle switch allows you to watch the progression of the free

surface front of the fluid. This option is available only if you run a 3D solution. The figure shown here illustrates the free surface of a die cast part. ENCLOSURE This toggle switch allows you to visualize the enclosure mesh, if one is present. This is only used for radiation problems. UNITS UNITS is activated by clicking on it. This results in the immediate action to display a dialog box containing a list of the unit of measure types. Next to each category of units is a rotary toggle switch which will display the available options for each of the categories. Successive clicks on these toggle switches will cycle through the available options. The UNITS parameters and the available options for each parameter will be presented here. For convenience in presentation, they will be presented in alphabetical order. HEAT FLUX--specifies the heat flux units to be used in the outputs. Choose from: { W/m**2 | cal/cm**2/sec | cal/mm**2/sec | Btu/ft**2/sec | Btu/in**2/sec | cal/cm**2/min | cal/mm**2/min | Btu/ft**2/min | Btu/in**2/min} The default is specified in QUNITS in the prefixp.dat file. PRESSURE--specifies the pressure units to be used in the outputs. Choose from: {N/m**2 | Pa | KPa | MPa | bar | dyne/cm**2 | atm | psia | Ksi | lb/ft**2} The default is specified in PUNITS in the prefixp.dat file. STRESS--specifies the stress units to be used in the outputs. USING VIEW CAST, PAGE 7 - 21

PARAMETERS

Choose from: {N/m**2 | Pa | Kpa | Mpa | bar | dyne | cm**2 | atm | psia | Ksi | lb/ft**2} The default is N/m**2 . TEMPERATURE--specifies the temperature units to be used in the outputs. Choose from: {C | F | R | K} The default is specified in TUNITS in the prefixp.dat file. VELOCITY--specifies the velocity units to be used in the outputs. Choose from: {m/sec | cm/sec | mm/sec | ft/sec | in /sec | m/min | cm/min | mm/min | ft/min | in/min} The default is specified in VUNITS in the prefixp.dat file. You may close this display and move to another function of ViewCAST by clicking the appropriate Main Function Banner. CONTINUOUS CONTINUOUS is a toggle switch which toggles between CONTINUOUS and SINGLE STEP modes of displaying contours and vectors. In the CONTINUOUS mode, contour and/or vector plots which are viewed in a time sequence will be displayed from the starting to the ending time level without user intervention. This allows you to view the results as though they were animated. In the SINGLE STEP mode, you can step forward or backward between time levels. This is useful if you want to study one image at a time or to obtain a hard copy of the image. Successive clicks on this menu option will toggle between CONTINUOUS and SINGLE STEP.

PAGE 7 - 22


PARAMETERS

ADJUST COLORS ADJUST COLORS allows you to customize the individual colors in the spectrum. You can then save your modified spectrum in a named file. You can create as many different spectra as you like.

When you select ADJUST COLORS, the display illustrated above is presented. The vertical color bar on the right shows the existing colors in the spectrum. To edit a color, click on the desired color entry in the vertical color bar. The selected color will be highlighted with a white border and that color will be displayed in the display box. This display box, appearing horizontally in the window allows you to adjust the red, green, and blue (RGB) values of the color using the three slider bars. You may move the sliders by clicking and holding the left mouse button when the cursor is over the slider knob. While you are depressing the mouse button, you may drag the knob in either direction. You may also increment and decrement these values by a value of one by clicking on the right or left arrows (><). The color square in the horizontal window changes instantaneously as the RGB values change. The current RGB value, between 0 and 255, for each color are displayed above the respective slider bar. When you are satisfied with the appearance of the color, click on the SAVE push button in the horizontal window. The modified color will be placed in the vertical color bar and the next color in the color bar will be loaded for editing. USING VIEW CAST, PAGE 7 - 23

PARAMETERS

You may also move directly to a particular color by clicking on it. Once you have finished modifying the colors in the spectrum, you can save this set by clicking the STORE push button. A Text Input window will be displayed. In this window, enter a file name and press ENTER. You type in any name without an extension, the extension ‘color’ will be added to the name you give. This file will be located in the ProPATH directory, which is where all the other ProCAST libraries are kept. The default color spectrum is kept in a file named view.color. A previously generated spectrum can be read back in by pressing the READ button. The same Text Input window will be displayed for you to enter the filename. Type the desired file name, without extension, and press ENTER. Once loaded, a previously defined spectrum may be modified and saved. You may close the ADJUST COLORS function without saving any changes by clicking the QUIT push button. You may also select another ViewCAST function from the Main Function Banner. FEATURE ANGLE FEATURE ANGLE allows you to specify which element edges of a mesh will appear in a plot. Sometimes it is desirable to see the finite element mesh superimposed on a plot of the results to aid in locating various phenomena. Other times, the mesh adds visual clutter. The FEATURE ANGLE function lets you control how much of the mesh you see. When you select FEATURE ANGLE, the slider bar illustrated here is displayed. Values available range from 0 to 180 degrees. The edge between two element faces will be drawn in the plot if the angle between the normals of the two faces is greater than or equal to the feature angle. A feature angle of zero will cause all element edges to be displayed. You may move the slider by clicking and holding the left mouse button when the cursor is over the slider knob. While you are depressing the mouse button, you may drag the knob in either direction. You may also increment and decrement these values by a value of one by clicking on the right or left arrows (><). The current value of this angle is displayed above the slider bar. When you are satisfied with the angle, click on the APPLY push button. You may close this display without changing the angle by clicking the CANCEL push button or by selecting another ViewCAST function from PAGE 7 - 24


PARAMETERS

the Main Function banner. COLOR VECTORS COLOR VECTORS enables you to control the appearance of vector plots. When you select COLOR VECTORS a sub-menu of coloring options is displayed, as shown here, is displayed. WHITE: the vectors will be drawn in white if a contour option has also been selected. The length of the vector will indicate the relative magnitude and the orientation will show the direction. MAGNITUDE: if vector quantities are being plotted without contours, they can be colored by their magnitude. The color spectrum on the right of the picture will show the correspondence between color and magnitude. TEMPERATURE: if fluid velocity vectors are being plotted without contours, they can be colored according to the nodal temperatures. This type of plot provides a great deal of visual information. PRESSURE: if fluid velocity vectors are being plotted without contours, they can be colored according to the nodal pressures. These menu options are mutually exclusive. The checkbox for the option selected will be highlighted. You may close this display by selecting another ViewCAST function from the Main Funtion banner. ALL VECTORS ALL VECTORS is a toggle switch which toggles between ALL VECTORS and SURFACE VECTORS. When the ALL VECTORS option is active, the vectors are drawn from every node in the active materials of the problem. When the SURFACE VECTORS option is active, vectors are only drawn from the nodes on the visible surface of the mesh.


PARAMETERS

ROTATIONAL SYM ROTATIONAL SYM provides the capability for you to display an image of the full geometry of an object which you may have modeled using the rotational symmetry option. When you select this menu option, the list and dialog input box, shown here, will be displayed. ROTATIONAL SYM may be activated by toggling the first push button in the list to the ON position. The background of the ROTATIONAL SYM menu item will be highlighted in blue as a reminder. To enter a value, select the list item by clicking on it. The background of the selected entry will be highlighted in red. Then insert the cursor in the text input line, type the desired value, and press ENTER. The value you typed will be displayed in the respective entry in the list and the background of the next entry in the list will be highlighted in red. You may enter or change any value in the list by repeating the selecttype-ENTER procedure described above. The entries in this list define the following: SECTORS--you enter the number of times the piece is repeated around the axis of symmetry, counting the original piece as 1. DELETED SECTORS--allows you to obtain a view with a pie-shaped cutout by entering some number greater than 0. This number should be less than that given for SECTORS. X0, Y0, Z0, X1, Y1, Z1--specify the coordinates for two points that define an axis of symmetry. You may leave the ROTATIONAL SYM option by clicking another push button in the Main Function Banner.

PAGE 7 - 26


PARAMETERS

MIRROR SYM 1 and 2 MIRROR SYM provides the capability for you to display an image of the full geometry of an object which may have one or two planes of mirror symmetry. Both MIRROR SYM 1 and MIRROR SYM 2 operate in the same way. When you select either of these menu options, the list and dialog input box, shown here, will be displayed. MIRROR SYM may be activated by toggling the first push button in the list to the ON position. The background of an active MIRROR SYM menu item will be highlighted in blue as a reminder. To enter a value, select the list item by clicking on it. The background of the selected entry will be highlighted in red. Then insert the cursor in the text input line, type the desired value, and press ENTER. The value you typed will be displayed in the respective entry in the list and the background of the next entry in the list will be highlighted in red. You may enter or change any value in the list by repeating the selecttype-ENTER procedure described above. The entries in this list define the X, Y, and Z coordinates for three points that define a plane of symmetry. You may leave the MIRROR SYM option by clicking another push button in the Main Function Banner. DISPLACEMENT MAG. DISPLACEMENT MAG. provides the capability for you to control the magnification factor for deformations to the mesh in stress analysis problems. This option is only available for stress analysis problems. When you select this menu option a dialog input box, as illustrated here, will be displayed. To enter a value, insert the cursor in the text input line, type the desired value, and press ENTER. The default value is 20.Set this value to zero if you do not wish to see the mesh deform with time. You may leave the DISPLACEMENT MAG. option by clicking another push button in the Main Function Banner.


PARAMETERS

PARTICLES PARTICLES provides the capability for you to inject a single particle into a fluid stream. This “tracer bullet” allows you to observe the path of the particle over time. When you select this menu option, the list and dialog input box, shown here, will be displayed. PARTICLES may be activated by toggling the first push button in the list to the ON position. The background of the PARTICLES menu item will be highlighted in blue when it is active. To enter a value, select the list item by clicking on it. The background of the selected entry will be highlighted in red. Then insert the cursor in the text input line, type the desired value, and press ENTER. The value you typed will be displayed in the respective entry in the list and the background of the next entry in the list will be highlighted in red. You may enter or change any value in the list by repeating the selecttype-ENTER procedure described above. The entries in this list define the following: RADIUS--specifies the radius of the particle. DENSITY--specifies the density of the particle. DRAG COEF--specifies the drag coefficient the particle will exhibit. START TIME--specifies the time at which the particle will be injected into the fluid stream. INIT {X, Y, Z} VEL--specifies the initial velocity of the particle in each coordinate direction. NODE--specifies the node number where the particle is to be injected. You may leave the PARTICLES option by clicking another push button in the Main Function Banner.

PAGE 7 - 28


PARAMETERS

CUT-OFF

CUT-OFF provides the capability for you to specify a value which will be used as the threshold for the values to be displayed. You may designate that only values above this threshold will be displayed. Conversely, you may designate that only values below this threshold will be displayed. For example, the figure shown here was generated after the criterion value was set to display only values above .6. The figure shows the fraction solid which was above .6 at the time step this image was captured. When you select the CUT-OFF menu option, the list and dialog input box, shown here, will be displayed. To enter a value, insert the cursor in the text input line, type the desired value, and press ENTER. The value you entered will be displayed in the VALUE line. You must indicate whether values above or below this value are to be displayed. This is done by clicking the rotary toggle switch which is directly above the VALUE line. Successive clicks on this switch will result in choosing, ABOVE, BELOW, or OFF. The default is OFF. If this option is set to ABOVE or BELOW, the background of the CRITERION menu item will be highlighted in blue. You may leave the CRITERION option by clicking another push button in the Main Function Banner.


PARAMETERS

TITLES TITLES provides the capability to place up to ten titles on contour and vector plots. When you select TITLES, the window shown below is displayed.

For each title, you need to give X and Y screen coordinates and the text of the title to be displayed. This information is placed in the three columns of the input window respectively. The location for the title is measured in pixels from the top left corner of the graphics area to the lower left corner of the text string. You may type these coordinates manually or you can click on the X--Y push button and use the mouse to set the location with a click of the left mouse button. To enter a value in the table insert the cursor in the desired input box and type the desired value. You may enter or change any value in the list by highlighting and retyping the entry. You may clear a table entry by selecting the text to be deleted and pressing Delete on the keyboard. You may clear the entire table by pressing the CLEAR push button. Once you are satisfied with all the entries, press APPLY. Remarks

The PARAMETERS function of ViewCAST provides the capability to tailor the view of results obtained from ProCAST. It is important to note that these parameters do not change the geometry, simulation description, or any of the results data. These parameters do affect what you will see and how it will be displayed when you activate the VIEW component of ViewCAST.

Related Topics

PAGE 7 - 30


VIEW

VIEW Description

VIEW is a push button in the Main Function Banner. This function of ViewCAST displays contour and vector plots. The options in this menu enable you to manipulate the graphical output which is displayed in order to facilitate your analysis. The functions available from this menu will be discussed in this section.

Method

VIEW is activated by clicking on it. When VIEW is activated, the geometry will be displayed in the graphics display window and the menu, shown here, will be displayed on the right side of the window. The ROTATE, ZOOM, CENTER, DRAG, HIDDEN, and RESTORE capabilities are described in the VIEWING TOOLS section of this manual and will not be repeated here. When you select a function from this menu, depending upon the specific option, ViewCAST may display additional dialog boxes, option lists, data input windows, or sub-menus. These graphical interface tools will guide you through the use of the selected option. You may leave the VIEW function by clicking another push button in the Main Function Banner. Each of the VIEW menu items which are not described in the VIEWING TOOLS section of this manual will be discussed immediately below. PICTURE This menu option begins the contour and/or vector plotting process. The plot will be displayed based upon the contour or vector you have chosen and the parameters you set. Plotting will begin at the time step you specified and will be redrawn at the interval you specified in the STEPS menu of ViewCAST. The figures in this section of the manual are examples of the plots which are displayed as a result of selecting the PICTURE menu option. Once you have activated the picture function, you may click on the PAUSE push button in the Main Function Banner to stop the plotting process. XYZ PLANES USING VIEW CAST, PAGE 7 - 31

VIEW

This tool allows you to designate specific X, Y, and Z planes in the model for viewing. Viewing these crosssectional planes is a three step process: 1. Defining the planes: When you select the XYZ PLANES option from the VIEW menu an input box will be opened, as shown here. You define the plane(s) of interest by moving the slider buttons in the input box. As you move a slider button, ViewCAST will display a reference outline in the model. This allows you to position the plane in the area of interest. You may set a single plane or multiple planes in any or all of the X, Y, or Z axes. ViewCAST indicates that a plane has been defined by placing a small arrow head above the slider bar for the appropriate axis. As shown in the figure above, four planes have been defined along the X axis, and two planes have been defined along the Y and Z axes. 2. Activating the plane(s) to be shown: You may activate the planes along each or all of the axes for viewing by selecting the X, Y, or Z push buttons which are shown on the left-side of the input box. When you select these push buttons, the background will change to red., and 3. Viewing the PICTURE: After a plane has been defined and the desired axis has been activated, click on the PICTURE push button in the VIEW menu to display the desired cross-section. XYZ PLANE settings may be stored for future use by clicking the STORE push button in the input box. This will open an input box as shown here. Enter the file name to be given to this set of cross sections and click on the APPLY push button. Once you have saved a cross-section definition, you may READ it for subsequent viewing and analysis. When you click on the READ push button as shown in the figure above, an input box will open for you to enter the name of the cross-sectional definition to be read. The CLEAR push button in the input dialog box shown above, will clear all planes which may have been specified and resets the X, Y, and Z push buttons to the off position.

PAGE 7 - 32


VIEW

The figure shown here illustrates that four cross-sections have been

designated and subsequently displayed when the PICTURE menu option of ViewCAST was selected. ANYPLANE PLANE This tool allows you to define cross-sectional planes by selecting three points in the model. Viewing these cross-sectional planes is a three step process: 1. Defining the planes: When you select the ANYPLANE option from the VIEW menu an input box will be opened, as shown here. You define a plane by moving the cursor to each of three points in the model which define the plane of interest. Clicking the left mouse button will select a point in the model and highlight this point with a small + sign. When three points have been designated, an outline of the defined plane will be highlighted in the model. This is illustrated in the figure below.

You may define more than one plane by clicking the NEW push button in the input box and selecting three points in the model. USING VIEW CAST, PAGE 7 - 33

VIEW

2. Activating the plane to be shown: You may activate a defined cross-section for viewing by selecting the desired plane definition in the input box and clicking the OFF/ON toggle switch in the input box. Once you have selected an entry in this list, it will be highlighted with a red background. Note: It may be easier for you to select specific nodes by clicking the HIDDEN menu item in the VIEW menu. 3. Viewing the PICTURE: After a plane has been defined and activated, click on the PICTURE push button in the VIEW menu to display the desired cross-section. ANYPLANE settings may be stored for future use by clicking the STORE push button in the input box. This will open an input box similar to that shown for the XYZ PLANES function. Enter the name to be given to this set of cross sections and click on the APPLY push button. Once you have saved a cross-section definition, you may READ it for subsequent viewing and analysis. When you click on the READ push button as shown in the figure above, an input box will open for you to enter the name of the cross-sectional definition to be read. The DEL push button in the input dialog box shown above, will delete the plane definition which has been highlighted in the list. You may close the ANYPLANE list by clicking the QUIT push button. The figure shown here illustrates a the result of using ANYPLANE to

define and subsequently display a cross-section. You may alternate between the ANYPLANE input list and the PICTURE menu option to view alternative cross-sections.

PAGE 7 - 34


VIEW

ISOSURFACE This tool allows you to watch the progress of the mush zone during casting fill. To view an isosurface you must define the upper and lower values to be used as the limits for the view. Once these limits are set, you must then click on the PICTURE option in the VIEW menu. When you click on the ISOSURFACE push button in the VIEW menu an input box will be opened, as shown here. You define the limits of the mushy zone by highlighting VAL1, placing the cursor in the Edit Value input line, typing the desired value and pressing ENTER. You repeat this process for VAL2. These actions will place the entered values in the respective positions in the input box. When you have entered both of these limits, click on the DONE push button to close the display. Once these limits have been entered, you may click on the PICTURE option in the VIEW menu to observe the progress of the specified mushy zone in the casting. The example shown here illustrates the mushy zone. Notice that (according to the limits specified in this example) solidification has already begun in portions of the casting as seen in the extreme right side and bottom of the casting.

DISPLACEMENT This option is only available for stress analysis problems. It allows you to view the deformed mesh in red superimposed on the original mesh which is displayed in white. REDRAW This option redraws the image in the graphics display window. This is useful for refreshing the graphics area.


VIEW

1 VIEW This option is a rotary toggle button which allows you to specify 1, 2, or 4 views of the model for concurrent display. You may describe up to four different views of the model and the respective XYZ PLANES to be displayed for each view. Viewing multiple views of the model is a three step process: 1. Defining the views: To describe a view, press 1, 2, 3, or 4 on the keyboard. You will see the view number, which is displayed in the lower left-hand corner of the work window will change to correspond with the number you pressed. You may rotate or reposition the model to suit your needs. You may then specify the cross-sectional planes to be plotted for this view. Concurrent views two through four may be defined in the same manner by first pressing the appropriate number on the keyboard. 2. Activating the number of concurrent views to be displayed: Click on the 1 VIEW push button in the VIEW menu to select the desired number of concurrent views to be displayed. Successive clicks on this push button will cycle through the number of views. 3. Viewing the PICTURE: After the views have been defined and activated, click on the PICTURE push button in the VIEW menu to plot the displays.

As shown here, the work window is divided in quadrants, in this example four, to show the views which were defined. PAGE 7 - 36


VIEW

REPLAY This option allows you to load and replay a picture file. When you select this menu option, a file name input box is displayed. As shown here, you place the cursor in the input line, type the file name, and click on DONE. This will result in the immediate action to load and play the replay file. You may close the file name input box by clicking the QUIT push button. Remarks

The VIEW options of ViewCAST afford a variety of analytical tools for visualizing the results of your ProCAST simulation. It is important to note that you may move back and forth between the options of the VIEW menu as well as the STEPS, MATERIALS, and PARAMETERS functions of ViewCAST. ViewCAST makes it easy to change starting times, time step values, the materials to be displayed, cross-sections, as well as other attributes of the results to be displayed. For example, clicking on any ViewCAST menu bar push button during the PICTURE display, will stop the picture and open the selected menu. Once you have completed the desired change, you can restart the display activity by clicking on the VIEW push button and then click on the PICTURE menu entry.

Related Topics

PAUSE, CONTOUR, VECTOR, STEPS, PARAMETERS, MATERIALS


PAUSE

PAUSE Description

PAUSE is a push button in the Main Function Banner which suspends contour and/or vector plotting. When PAUSE is active, you may create replay files or postscript printer files containing the views and results which are being displayed. Plotting may be resumed by clicking PAUSE again. The functions available from this menu will be discussed in this section.

Method

PAUSE is activated by clicking on it. When PAUSE is activated, the option buttons, shown here, will be displayed in the lower-right side of the work window. These option buttons provide the capability to create a replay file, using the ST option, and/or to create the postscript file, using the P option. As shown here, when you select the ST function, a file name input box will be displayed. To create a replay file, place the cursor in the input line, type the file name and click on DONE. You may resume the animated display by clicking the PAUSE push button. You may close the file input box without entering a file name by clicking the QUIT push button. The P option results in the immediate action to create a postscript printer file. Once the file has been created you may resume the animated display by clicking the PAUSE push button.

Remarks

PAUSE may be used to temporarily suspend the animated updating of the picture. It is not necessary to resume the animation in order to make changes to parameters, steps, cross-sectional planes, or other capabilities available in ViewCAST. For example, if you pause the display and decide to change the interval step value, you may click on the STEPS push button in the Main Function Banner without first resuming the picture display.

Related Topics

PAGE 7 - 38


CONTOUR, VECTOR, STEPS, PARAMETERS, MATERIALS, VIEW

USING INVERSE MODELING

CHAPTER 8 USING INVERSE MODELING Description

The Inverse Modeling module of ProCAST allows you to determine thermophysical data or boundary conditions from simple well controlled temperature measurements.

Method

The INVERSE solver runs in a Unix session window. After you open the session window, the INVERSE calculation can be started using the following command at the session window prompt: inve {prefix} [ -b ] ENTER Prefix is a required parameter and you should enter the name of this project. -b is a command line option which specifies that INVERSE will be run in the background as a batch mode task. Do not use the UNIX ampersand (&) option to run proinve in the background.

Remarks

Inverse modeling allows you to use the thermal history generated by ProCAST as an input for deriving thermophysical properties, initial conditions, or boundary conditions. In order to perform the selected inverse calculations all other aspects of a problem must be set-up. This means that information about the following components of the problem must be defined. • geometry, • material properties, • interface heat transfers, • boundary conditions, • initial conditions, and • run parameters. You may use menu options in the MATERIALS, INTERFACE, BOUNDARY CONDITIONS, and RUN PARAMETERS menus to specify the component and properties to be calculated using the inverse methodology. Once a problem has been configured in PreCAST, you should run DataCAST to check the model for errors. The prefixid.dat file generated by PreCAST contains all of the inverse settings. In a manner similar to the PreCAST prefixd.dat file, the inverse settings file may be modified manually with a text editor. The format of the prefixid.dat file is described in Appendix K of this manual.

USING INVERSE MODELING, PAGE 7 - 1


Operational procedures and standards at your installation may specify additional start-up requirements such as passwords, working directory specifications, and project or file naming conventions. Consult your installation or network manager for these guidelines. There are three ways to monitor the status of the Inverse Calculation. Monitoring the calculation is a good practice for checking to determine that the calculation is stable and that convergence is progressing. Each of these three methods for monitoring this progress are described here. Using the status utility There is a small utility program which can be run to report the status of the INVERSE calculation. This utility may be started by opening a Unix session window, setting the current directory to the directory containing this problem’s prefix* files, and typing the following command at the session window prompt: statinve {prefix} ENTER This utility prints the status of the calculation by indicating whether it is still in progress or that it has been completed. It also provides additional information which includes: the number of iterations already calculated, the beta values of the last iteration, and the residual of the current iteration. The residual is the average temperature difference between the measured and the calculated curves based upon an average of all the steps and all the curves at the given iteration. The residual will decrease towards zero and is a good way to see how the convergence is reached. Note: If the calculation was interrupted by the user, it will display that the calculation is in progress.

Evolution of the beta values The beta values obtained at each iteration are stored in the file prefixir.dat. Accordingly, during the calculation, it is possible to use PostCAST to visualize the evolution of each beta value from the first iteration to the current iteration. From this plot, you can determine if the calculation is converging. The format of the file prefixir.dat is the same as that of the measurement. Curve “I: of the file prefixir.dat corresponds to the ith beta value. The residual is stored as the last curve of the prefixir.dat file. You can therefore graph the evolution of the residual as a function of the iterations.

PAGE 7 - 2



Comparison between the measurements and the calculated curves The goal of inverse modeling is to find the best set of beta values with which the calculated temperature curves will match the measured ones. At the end of each iteration, the calculated curves corresponding to the location of the measurement points are stored in the prefixic.dat file. This file is updated at each iteration. You can use PostCAST to visualize the comparison of the measured curves and the calculated curves by superimposing one on the other. During the first iteration the match between these two will be poor. Subsequent iterations should improve with the match at the end of the calculation being good.

Final Results At the end of the calculation, the final beta values correspond to the values of the last iteration in the prefixir.dat file. The quality of the convergence may be checked as described above and are considered good if the beta values are not changing much during the last iterations and if the residual is small. Note that the residual is measured in degrees and a residual of “1" means that the average difference between the measured and calculated curves is one degree. Depending upon the convergence tolerance which is chosen, it is possible that the beta values stay almost constant but oscillate around an average value and the calculation will be continued until the maximum number of iterations specified is reached. Based upon these initial results, for subsequent inverse calculations, is possible to reduce the maximum number of iterations in order to reduce the computing time required. If the inverse calculation is performed in a networked environment, it is advisable to run the calculation in a directory which is on the disk closest to the calculating CPU. This reduces the disk access delay which may occur through the network. It is always possible to run the calculation in the /tmp directory and then move the final results to the home directory of the user.

Related Topics

APPENDIX B, APPENDIX K, APPENDIX L

USING INVERSE MODELING, PAGE 7 - 3



PAGE 7 - 4


INSTALLING PROCAST

APPENDIX A INSTALLING ProCAST Create Installation Directory

Use the Unix system command to make a directory in which you will install ProCAST. The syntax for this command is: mkdir /directoryname ENTER The following example creates the directory “procast.” mkdir /procast ENTER After the directory has been created, make it the active directory. The syntax for this command is: cd /directoryname ENTER The following example changes to the procast directory. cd /procast ENTER

Extract ProCAST files

Mount the delivery tape and extract the files. The syntax for this command is: tar xvf /dev/tapeunitname ENTER The following example extracts the files from the tape unit “rst8.” tar xvf /dev/rst8 ENTER This should create two subdirectories called BIN and LIB.

Establish Access Authorizations

The BIN directory must have read and execute permissions for all authorized users. The files in the LIB directory, the LIB directory and the BIN directory need read and write permissions for all authorized users. The following example changes the permission code for the files in the BIN directory. chmod 555 BIN/* ENTER (Gives read + execute) The following example changes the permission code for the files in the LIB directory. chmod 666 LIB/* ENTER (Gives read + write) The following example changes the permission codes for the BIN and LIB directories. chmod 777 BIN LIB ENTER (Gives read + write + execute) To perform these commands, you must be the owner of the files and directories. The superuser can use the chown command to assign the correct ownership for these files and directories.

APPENDICES, PAGE A - 5

INSTALLING PROCAST

Modify PATH Statement

The following lines should be put into the .cshrc file of each user if they are using the C shell: setenv ProPATH /procast/LIB setenv ProBIN /procast/BIN Alternatively, if the Bourne shell is being used, the following lines should be put in the .profile file: ProPATH=/procast/LIB export ProPATH ProBIN=/procast/BIN export ProBIN You should make sure that the path names are the same as the installation directory.

Establish PATH

The path “/procast/BIN” needs to be in the set path command in either the .login or .cshrc files of all users or in the PATH command in the .profile file. You should make sure that the path names are the same as the installation directory.

Unlock ProCAST

To unlock ProCAST, set the ProPATH environment variable, run the unlocking program, and supply the unique unlock code. The syntax for this command is as follows: pro_enable unlockcode ENTER The unlock code will be provided to you by UES Software and it is calculated for your unique environment.

PAGE A - 6


PROCAST FILE USAGE

APPENDIX B ProCAST FILE USAGE This appendix presents a profile of the file usage for each component of ProCAST. Presented in tabular form, the name of the ProCAST component is displayed in the top of each table. Input files are listed in column one. The file description for the input file is presented in column two. Output files are listed in column three. File descriptions for the output files are presented in column four if they are different than the descriptions of the input files. The file usage for each ProCAST component are shown below. PreCAST Input Files

Description

Output Files

Description

prefix.out

PATRAN or ANVIL neutral file which describes the model geometry

prefixd.dat

Problem description file

prefix.unv

IDEAS universal file which describes the model geometry

prefixp.dat

Problem run file

prefix.ans

ANSYS node and element files

pre.err

Error log file

prefix.14


prefix.15


pre.scr

Menu descriptions for PreCAST

pre.edf

Editor descriptions for PreCAST

promat.db

ProCAST supplied material properties database

matl.db

User's material properties database

matl.db

matl.idx

User’s material properties index

matl.idx

micro.db

Micromodel material properties database

micro.db

micro.idx

Micromodel material properties index

micro.idx

intf.db

Interface heat transfer coefficients database

intf.db

intf.idx

Interface heat transfer coefficients index

intf.idx

bndry.db

Boundary conditions database

bndry.db

bndry.idx

Boundary conditions index

bndry.idx

encl.db

Enclosure properties database

encl.db

encl.idx

Enclosure properties index

encl.idx

stress.db

Stress material properties database

stress.db

stress.idx

Stress material properties index

stress.idx

DataCAST Input Files prefixd.dat

Description

Output Files

Description


APPENDICES, PAGE B - 1

PROCAST FILE USAGE

DataCAST Input Files

Description

Output Files

Description

prefixd.out

Printed output from DataCAST

prefixg.unf

Unformatted geometry file

prefixd.unf

Unformatted time step file

prefixt.unf

Unformatted temperature file

prefixu.unf

Unformatted u---velocity file

prefixv.unf

Unformatted v---velocity file

prefixw.unf

Unformatted w---velocity file

prefixp.unf

Unformatted pressure file

prefixk.unf

Unformatted turbulent kinetic energy file

prefixe.unf

Unformatted turbulent dissipation rate file

prefixf.unf

Unformatted fluid fraction file

prefixq.unf

Unformatted heat flux file

prefixo.unf

Unformatted file of nodal coordinate offsets for enclosure elements

prefixs.unf

Unformatted file of nodal coordinate offsets for moving solid elements

ProCAST Input Files

Description

Output Files

prefixp.dat

Run parameters

prefix.unf

Unformatted files, where =g, d, t, u, v, w, p, f, k, e, q, o, s as in DataCAST

prefix.unf

prefix.ctoc

Unformatted radiation view factor information

prefix.ctoc

prefix.fic

Fictitious mold information

prefix.fic

prefix.sel

Highest filled element when FREESF = 2

prefix.sel

prefix.fom

Lost foam information

prefix.fom

prefixa.unf

Unformatted freezing time file

prefixa.unf

prefixb.unf

Unformatted dissolved gas bubble file

prefixb.unf

prefixc.unf

Unformatted macro porosity file

prefixc.unf

prefixfs.unf

Unformatted fraction solid file

prefixfs.unf

prefixr.unf

Unformatted compressible density file

prefixr.unf

prefixn.unf

Unformatted non-Newtonian shear rate and viscosity file

prefixn.unf

prefixv.unf

Unformatted turbulent viscosity file

prefixtv.unf

prefixeng.unf

Unformated electric potential file

prefixeng.unf

prefixmg.unf

Unformatted magnetic potential file

prefixmg.unf

PAGE B - 2


Description

PROCAST FILE USAGE

ProCAST Input Files

Description

Output Files

prefixx.unf

Unformatted x displacement file

prefixx.unf

prefixy.unf

Unformatted y displacement file

prefixy.unf

prefixz.unf

Unformatted z displacement file

prefixz.unf

prefixgs.unf

Unformatted stress file

prefixgs.unf

prefixgn.unf

Unformatted effective plastic strain file

prefixgn.unf

prefixst.unf

Unformatted total load file

prefixst.unf

prefixsr.unf

Unformatted stress source term file

prefixsr.unf

prefixcp.unf

Unformatted contact pressure file

prefixcp.unf

Description

prefixp.out

Printed output from ProCAST

prefix.serr

Row sum error view factor file

prefix.view

Group to group view factor file

prefix.vf

Face to face view factor file

PostCAST Input Files

Description

prefix.unf

Unformatted files, where = g, d, t, u, v, w, p, f, q as in DataCAST

post.scr

Screen descriptions for PostCAST

post.edf

Editor descriptions for PostCAST

prefix.serr

Row sum error file

Output Files

Description

prefixe.ntl

Row sum error file for postprocessing use

prefixfs.unf

Unformatted fraction solid file

prefixg.ntl

Geometry neutral file for postprocessing use

prefixi.ntl

Isochron results neutral file

prefixm.ntl

Mapping function results neutral file

prefixm.unf

Mapping function results unformatted file

prefixl.ntl

Feeding length results neutral file

prefixl.unf

Feeding length results unformatted file

prefixr.ntl

Radiation model geometry file for model check-out

prefix.ntl

Dependent variable results neutral file, where = t, u, v, w, p, q

prefixi.log

Temperature log


PROCAST FILE USAGE

PostCAST Input Files

Description

Output Files

Description

prefixm.log

Mapping function log

prefixl.log

Feeding length log

prefix.log

Analysis time log for use with dependent variable results neutral files, where = t, u, v, w, p, q

post.err prefix.tt

Temperature, velocity, pressure, or fraction solid versus time file

ViewCAST Input Files

Description

Output Files

prefix.unf

Unformatted files, where = g, d, t, u, v, w, p, f, q as in DataCAST

view.scr

Screen descriptions for ViewCAST

view.edf

Editor descriptions for ViewCAST

prefixi.ntl

Isochron results neutral file

prefixm.ntl

Mapping function results neutral file

prefixi.log

Temperature log for use with the isochron neutral file

prefixm.log

Mapping function log for use with the mapper neutral file

prefix.serr

Row sum error file

prefix.view

Group to group view factor file

view.color

Color spectrum file ( contains RGB values )

prefix.unf

Unformatted files, where = a, b, c, r, n, tv, mg, x, y, z, gs, gn, as in ProCAST

Description

view.color

INVERSE Input Files

Description

prefixd.dat


prefixim.dat

Contains the node numbers or node coordinates corresponding to the location of the measurement points.

prefixid.dat

Contains the inverse settings.

PAGE B - 4


Output Files

Description

prefixir.dat

Contains the evolutions of the beta values along the iterations. It also contains the evolution of the residual.

prefix.stat

Contains information on the status of the inverse calculation.

PROCAST FILE USAGE

INVERSE Input Files

Description

Output Files

Description

prefixic.dat

Contains the calculated temperature evolutions (of the last calculated iteration) corresponding to the locations of the measured curves.

prefix.list

This file is created, if the inverse calculation is performed in the background, to store the printout which normally appears on the workstation screen. This file is only written when the workstation buffer is unloaded.


PROCAST FILE USAGE


PAGE B - 6


MATHEMATICAL FORMULATIONS

APPENDIX C MATHEMATICAL FORMULATIONS

Section 1: Energy Equations 1.

Transient linear

'cp T /

t

[ k / T ] q ( x ) 0

C.1.1

where

T = vector of nodal temperatures q(x) = spatially varying volumetric heat source

/

x

y

z

C.1.2

in Cartesian coordinates ' = constant density cp = constant specific heat t = time k = constant conductivity 2.

Transient non-linear conduction

' H T / [ k /

T t where

T ] q(x) 0

C.1.3

' = '0 f(T), constant or temperature dependent density k = k0 f(T), constant or temperature dependent conductivity H = enthalpy, a function of temperature, which encompasses the effects of specific and latent heat T

H( T )

cp d - L[ 1 f s (T )]

C.1.4

P

0

L = latent heat fs = fraction solidified 3.

Transient laminar advection-diffusion

APPENDICES, PAGE C - 1


' 0H 'ui 0H /( k / 0t

0xi

T) q 0

C.1.5

where

ui = fl ui,liq = component of superficial velocity fl = fraction liquid ui,liq = actual liquid velocity 4.

Transient turbulent advection-diffusion

' 0H 'ui 0H / 0t

0xi

k

µT

)T

/T q 0

C.1.6

where µT = eddy viscosity )T = turbulent Prandtl number Section 2: Continuity Equation Conservation of mass is enforced through the continuity equation:

0' 0( 'ui ) 0 0xi 0t

C.2.1

Section 3: Momentum Equations The full Navier-Stokes equations are given by:

0( 'ui ) 0 (uj 'ui p ij )ij ) 'gi 0t 0xj where

)ij =

C.3.1

Stokes viscous stress tensor including the Reynolds stress approximation and assuming the bulk viscosity is negligible

)ij

µ

0ui 0uj 0u 0u 2 µ k ij µ T i 0xj 0xi 0xj 3 0xk

C.3.2

ij = Kronecker delta p = pressure gi = gravitational acceleration Expanding the differentials on the advection term and using the continuity equation to simplify yields:

PAGE C - 2



'

0ui 0u ' uj i 0 ( p ij )ij ) 'gi 0t 0xj 0xj

C.3.3

Assuming that the spatial derivatives of viscosity are small and that the fluid is nearly incompressible, many terms in the viscous stress tensor can be neglected. A source term is added to the standard momentum equation to simulate the effect of flow in mushy regions and to drive the velocities to zero when the material is fully solid. This gives the final form of the momentum equation as used in ProCAST:

'

0ui 0u 0u 'uj i 0 p ij (µ µT) i 'gi µ ui K 0t 0xj 0xj 0xj

C.3.4

where

K = permeability The permeability is calculated using the Kozeny-Carmen equation 3

K

fl

5 Ms (1 f l )2 6 Ms

Dp 2

C.3.5

where

Ms = surface to volume ratio of solid structure = shape factor Dp = characteristic dimension Assuming conically shaped dendrite arms with an average diameter of 100 microns, Ms = 600cm-

1

Section 4: Turbulent Kinetic Energy The conservation equation for turbulent kinetic energy is given by:

0('k) u 0('k) 0 j 0t 0x j 0xj

µT 0k )k 0xj

µTG '

C.4.1

where



k

u 1 ,v 1 ,w 1

)k

G

1 (u 12 v 12 w 12 ) 2 fluctuating velocity components Prandtl number of turbulent kinetic energy, typically set to 1.0 0ui 0uj 0ui

turbulence generation rate 0xj 0xi 0xj turbulence dissipation rate

Section 5: Turbulence Dissipation Rate The differential equation for calculating the dissipation rate is as follows:

0(') u 0(') 0 µT 0 (C µ G C ') 1 T 2 j k 0t 0xj 0xj ) 0xj

C.5.1

where ) = Prandtl number for turbulence dissipation rate, typically set to 1.3. Default values are: C1 = 1.44 and C2 = 1.92 Section 6: Eddy Viscosity The turbulent eddy viscosity is calculated from the turbulent kinetic energy and dissipation rate as follows: µT

Cµ 'k 2

C.6.1

where

Cµ = 0.09 is a default Section 7: Non-Newtonian With non-Newtonian flow, the shear stress is a nonlinear function of the strain rate, represented by

-

PAGE C - 4


C.7.1


The current version of ProCAST contains an implementation of the Carreau-Yasuda correlation in which the viscosity is given by

(0 )[1 ( )a ]

n 1 a

C.7.2

where 0 = zero strain rate viscosity = infinite strain rate viscosity = phase shift coefficient a = Yasuda coefficient n = power law coefficient In ProCAST, all five of these coefficients can be constants or functions of temperature. The strain rate, as it appears in the correlation, is taken to be the magnitude of the strain rate tensor:

1 2

M

M

i

j

ij ji

.5

1 ( :

.5

2

C.7.3

where

.

0u 0u 0x 0x

0v 0u 0x 0y

0w 0u 0x 0z

0u 0v 0y 0x

0v 0v 0y 0y

0w 0v 0y 0z

0u 0w 0z 0x

0v 0w 0z 0y

0w 0w 0z 0z

C.7.4

The shear force terms in the momentum equations take on the following form:

0 (- ) 0 (- ) 0 (- ) 0x xx 0y yx 0z zx 0 (- ) 0 (- ) 0 (- ) Y : 0x xy 0y yy 0z zy 0 (- ) 0 (- ) 0 (- ) Z : 0x xz 0y yz 0z zz X :

C.7.5



Using the x-momentum term as an example and the stress-strain relationship shown previously, the following expansion is possible:

0 0u 0u 0 0v 0u 0 0w 0u

0x 0z 0x 0x 0y 0x 0y 0z 0x 0 0u 0 0u 0 0u 0x 0x 0y 0y 0z 0z

C.7.6

0 0u 0 0v 0 0w 0x 0x 0y 0x 0z 0x The first three terms on the right hand side are the same as appear in the Newtonian Navier-Stokes formulation. The last three terms can be simplified somewhat by expanding them further:

0 0u 0 0v 0 0w

0x 0x 0y 0x 0z 0x

0 0u 0v 0w 0u 0 0v 0 0w 0 0z 0x 0x 0x 0y 0x 0z 0x 0x 0y

C.7.7

Assuming that the densification rate, 0' / 0t , is negligible, then the first term on the right hand side vanishes from continuity. This leaves a non-Newtonian contribution to the shear force of the form:

/x V # /

C.7.8

Similar terms arise for the y and z momentum equations as well. A dissipation term is also added to the energy equation of the form:

0 2 0u 0x

0v 0u 0x 0y

PAGE C - 6


2

2

0v 0y

0u 0w 0z 0x

0w 0z

2

2

2

0v 0w 0z 0y

C.7.9 2


Section 8: Initial and Boundary Conditions 1.

Initial conditions

T (x,0) u (x,0) v (x,0) w (x,0) p (x,0)

2.

T0 (x) u0 (x) v0 (x) w0 (x) p0 (x)

C.8.1

Fixed temperature boundary condition

T (x) T d (x) f (t), on

1

C.8.2

where

1 = some subset of the total boundary Td(x) = specified temperature vector f(T) = time function This is also known as a Dirichlet boundary condition. In a steady state problem, there is no time function modifying the specified temperatures.

3.

Fixed velocity boundary condition

V (x) Vd (x) f (t), on

1

C.8.3

1

C.8.4

where Vd(x) = specified velocity vector f(t) = time function 4.

Fixed pressure boundary condition

P (x) Pd (x) f (t), on

where

Pd(x) = specified pressure vector f(T) = time function



5.

Fixed turbulent kinetic energy boundary condition

(x) d (x)

where

f (t), on

1

C.8.5

d(x) =

specified turbulent kinetic energy vector f(t) = time function By default, the turbulent kinetic energy is taken as 5% of the total kinetic energy of the flow, that is

1 (.05V )2 2

C.8.6

where V = total velocity magnitude 6.

Fixed turbulent dissipation rate boundary condition

(x) d (x) f (t),

where

on

1

C.8.7

d(x) =

specified turbulent dissipation rate vector f(T) = time function By default, the turbulent dissipation rate is calculated as

where

3

cµ 2 /

C.8.8

= a characteristic length which is assumed to be 1.0% of the smallest dimension of the opening cµ = the run parameter CMU

PAGE C - 8



7.

Specified heat flux boundary condition

k / T # nˆ qn f (t), on 2

C.8.9

where

qn specified heat flux nˆ unit vector normal to the surface

2 some subset of the total boundary

This is also known as a Neumann boundary condition. 8.

Convective heat flux boundary condition

k / T # nˆ h f (t) g (T ) [T Ta], on 2

C.8.10

where

h = convection (film) coefficient g(T) = temperature function Ta = ambient temperature, which can be a function of time. 9.

Radiation heat flux boundary condition

k / T # nˆ ) g (T ) [T 2 Ta2 ] [T Ta ] [T Ta ], on 2 where

C.8.11

)= =

Stefan-Boltzman constant emissivity This is the "simple" radiation model in which it is assumed that there is only one ambient temperature present. Thus, the view factor is equal to one.



Section 9: The View Factor Radiation Model For the more complex view factor radiation capability, ProCAST uses a net flux model. Rather than tracking the reflected radiant energy from surface to surface, an overall energy balance for each participating surface is considered. At a particular surface i, the radiant energy being received is denoted qin, i. The outgoing flux is qout, i. The net radiative heat flux is the difference of these two.

qnet, i qout, i qin, i

C.9.1

Utilizing the diffuse, grey-body approximation, the outgoing radiant energy can be expressed as

qout, i

) i Ti4

(1

i ) qin, i

C.9.2

The first term in (C.9.2) represents the radiant energy which comes from direct emission. The second term is the portion of the incoming radiant energy which is being reflected by surface i. The incoming radiant energy is a combination of the outgoing radiant energy from all participating surfaces being intercepted by surface i. Specifically, the view factor Fi-j is the fraction of the radiant energy leaving surface j which impinges on surface i. Thus,

qin, i

N M

j 1

Fi j qout, j

C.9.3

where

N = total number of surfaces participating in the radiation model and the view factors are calculated from the following integral. Fi j

cos

1 Ai Aj

Ai

j cos i %r 2

d Ai d Aj

C.9.4

where

Ai = area of surface i i = polar angle between the normal to surface i and the line between i and j r = magnitude of the vector between surfaces i and j Traditionally, (C.9.4) is evaluated by numerical integration, either in the form shown or converted into an equivalent line integral. In ProCAST, the view factors are computed using a proprietary technique.

PAGE C - 10



Solving (C.9.2) for qin, i yields:

qin, i

1 1

[qout, i

i

) i Ti4 ]

C.9.5

Combining (C.9.5) with (C.9.3) gives a relationship involving the outgoing radiant fluxes only. These outgoing fluxes are known as radiosities. The final form is N M

j 1

[ ij (1

i ) Fi j ] qout, j )i Ti4

C.9.6

The Kronecker delta, i,j, has been included to incorporate the diagonal term. Since there are equations of the form (C.9.6), a simultaneous solution is required for a large non-symmetric system. Because of the reciprocity relation, Ai Fi-j = Aj Fj-i (C.9.6) can be transformed into a symmetric form which is more economical to solve. Multiplying (C.9.6) by

Ai (1

C.9.7

i )

yields: N M

j 1

Ai (1

i )

ij

Ai Fi j qout, j

i Ai ) Ti4 (1 i )

C.9.8

which is solved for the vector of radiosities, qout, j. The net radiant flux is obtained by combining (C.9.1) and (C.9.5), giving

qnet, i

i 1

i

[)T i qout, i ] 4

C.9.9

This heat flux then appears as a boundary condition for the heat conduction analysis in ProCAST.



Section 10: Finite Element Discretization Conduction The solution domain, 6, is divided into a set of non-overlapping subregions which completely fill the space. In each of these elements, temperatures are interpolated from values at discrete nodal locations. This yields a temperature field which approximates the exact solution.

T ( x, t ) Ni (x) T i (t)

C.10.1

where

Ni = interpolating or "shape" functions Ti = nodal values of temperature Repeated indices in a term indicate the application of the Einstein summation convention. The particular shape functions employed are a consequence of the element types. Currently, ProCAST supports linear brick, tetrahedral, and wedge elements and quadratic tetrahedral elements. The following development will concentrate on the non-linear, transient heat conduction case. Inserting the approximate solution (C.10.1) into the governing field and boundary condition equations (C.1.3), (C.8.9--C.8.11), produces a residual error. This error is minimized in an average sense by the Method of Weighted Residuals, applying the Galerkin procedure of using the shape functions, Ni, as the weighting functions. This results in the symmetric matrix system

C T K T F

C.10.2

where

C = capacitance matrix with terms

' dH

Cij

dT

6

Ni Nj d 6

C.10.3

K = conductivity matrix with terms

/ N i # (k / N j ) d 6

Kij

6

h Ni Nj d 2

C.10.4

2

F = source vector with terms Ni (q hT a ) d 2

Fi

2

T time derivative of the vector of nodal temperatures In (C.10.4) and (C.10.5), h combines the effects of Newtonian and radiation heat transfer.

PAGE C - 12


C.10.5


The integrations are performed on an element-by-element basis and assembled to form the global matrices. Typically, these integrations are too complex to perform analytically. Recourse is taken to numerical integration techniques, which involve an isoparametric mapping to a local, element-based coordinate system. Details of this approach can be found in any standard finite element text book. One feature of ProCAST which particularly enhances its utility for casting simulations is a coincident node technique for handling the mold-metal interface and parting surfaces. Along the desired thermal break interface, 3, a second set of spatially coincident nodes is added to the original nodal topology. The original nodes would be assigned to the elements on one side of the interface, the metal for example, and the second set to the other side. A Newtonian heat flux relation between the two sets is incorporated into the conductivity matrix by an integration on 3,

K K

hc Ni Nj

3

1 Nk d 3 2

C.10.6

where hc coincident interface heat transfer coefficient. This may be a function of time and/or temperature. Node k is coincident to node j. The advantages of using coincident nodes rather than thin elements at the interface are that it is more economical in terms of CPU time, and it is easier to specify when using commercial preprocessing packages to create the finite element mesh. In ProCAST, this technique will automatically be employed at the interface of dissimilar materials if the user desires. Momentum Applying Galerkin's method to the momentum equation gives the following expression:

Ni

' N 0uj dV j fl

0t

Ni

' 2 fl

Ni 'gj dV

uk

0uj dV 0xk

0p Ni dV 0x

Ni

0 µ1 0(Nj uj) dV

0x k f l 0x k

µ1 Ni Nj uj dV K

C.10.7

where µ1 = (µ + µT)



A streamline upwind approximation is used in the advection term:

Ni

' 2

fl

uk

0(Nj uj) ' u 0u dV 2 s 0s 0xk fl

Ni dV

C.10.8

where

us = streamline velocity s = streamline coordinate The divergence theorem is applied to the diffusion term of the momentum equation so that the weighting functions and interpolating functions will be of the same order.

Ni

0 µ1 0(Nj uj ) dV 0xk fl 0xk

0Ni µ1 0Nj u dV 0xk fl 0xk j

Nj

0(Nj uj) µ1 # ndS 0xk fl

C.10.9

The final discretized momentum equation has the form: Mu (D A C )u Sg Sp 0

C.10.10

where

Mij

' N N dV

Dij

µ1 0Ni 0Nj dV f l 0xk 0xk

Aii

i

fl

's 2 fl

Cij

us

j

1 s

Ni dV P

µ1 Ni Nj dV K

Ni 'gk dV

Sg, i P

Sp , i

PAGE C - 14


Ni

0p dV 0xk

C.10.11


Using a two level time stepping method and solving for a correction value yields the following equation form: M

(u n 1 u n ) ( D A C ) [u n 1 (1 t

)u n ]

Sg Sp 0

(M/ t)u n 1 ( D A C ) u n 1 (M/ t)u n ( D A C ) (1

)u n

Sg Sp

C.10.12

[(M/ t) ( D A C ) ] u n 1 ( D A C )u n Sg Sp

Pressure If the discretized momentum equations are considered in terms of the resulting coefficients, Bij, and nodal velocities, uj, then the effect of pressure gradients may be separated out as:

Bii ui ui uˆ uˆ

M

1 Bii M

0p dV 0x 0p dV uˆ K 0p Ni i 0x 0x

Bij uj f i

Bij uj f i Bii

Ni

, Ki

C.10.13

Ni dV P

Bii

It has been assumed momentarily that the pressure gradient is constant under the integral. First, the continuity equation is discretized using Galerkin's method of weighted residuals and Green's Lemma:

Ni Ni

0' dV 0t

0' 0('uk ) dV

0xk 0t Ni ( 'uk ) # n dS

'uk

C.10.14

0Ni dV 0 0xk

Substituting the velocity correction relation above into the discretized continuity equation yields the pressure equation:

'

uˆk Kk

0p 0Ni dV

0xk 0xk

0N 'Kk 0p i dV

0xk 0xk

Ni ('uk ) # n dS

0N ' uˆ k i dV 0xk

Ni ('uk) # n dS

Ni

0' dV 0t 0' dV Ni 0t

C.10.15



This is solved in a correction form as: D p n 1 D p n Su S'

C.10.16

where:

Dij

'Kk

0Ni 0Nj dV 0xk 0xk

Su, i

'uˆk

0Ni dV 0xk

Ss, i

Ni ( 'uk ) # n dS

Sp, i

Ni

C.10.17

0' dV 0t

Section 11: Time Stepping Algorithm The first order differential equation system which is obtained from the finite element spatial discretization, (C.10.2), is numerically integrated by a two level predictor-corrector scheme. Predictor Step [C

t K ] T0n 1

[C

t (1 ) K ]T n F

C.11.1

where C, K, and F are evaluated with intermediate temperature values at time level n n1 T0

predicted temperature vector t current time step

Corrector Step [C

t K ] Tpn 1

[C

t (1 ) K ]T n F

where C, K, and F are evaluated with intermediate temperature values T~ n1 T~ T p (1 ) T n , [0.0,1.0] n1

Tp

PAGE C - 16

corrected temperature vector


C.11.2


The solution vector is corrected until either the maximum of number of corrections is reached or the maximum difference in temperatures between two successive iterations is less than a user-specified convergence criterion. This algorithm automatically adjusts the time step according to the number of corrector iterations that were required on the previous step. If the maximum number of corrections is exceeded, the time step is reduced and the step attempted again. The value of , selected from the range of 0.0 to 1.0, determines the nature of the algorithm. Some familiar two-level schemes which may be recovered are as follows:

0.0, forward difference, explicit 1 , central difference 2

2 , Galerkin 3

1.0, backward difference, fully implicit

If capacitance matrix is lumped with the forward difference scheme, the global system matrix becomes diagonal and is therefore rapidly inverted. However, the time step restriction to ensure stability can be unacceptably severe. For unconditional stability, it is required that 1 . 2 The central difference scheme is the only two-level method with second order accuracy and is thus recommended in general. However, it also has a time step restriction to prevent oscillation. The time step is governed by the eigenvalue spectrum of the system matrix. In a typical casting simulation, the high frequency modes, which correspond to large eigenvalues, quickly decrease in amplitude. This permits a gradual increase in the time step from a small initial value without producing oscillations. The backward difference scheme has no stability or oscillatory time step restriction and is therefore always "safe." However, it is only first order accurate and tends to smooth out results which should be sharply varying. An Implicit-Explicit Algorithm is available, based on this two-level scheme. It is implemented simply by assigning values of independently to each element. For = 0.0, the element capacitance matrix is lumped, contributing only diagonal terms to the system matrix. This speeds up the solution of the system when a profile based solver is used. In casting simulations, it is often possible to treat the mold elements explicitly because of the large difference in material properties between metal and mold. A substantial reduction in computational costs can be realized if this technique is employed.



Section 12: Electromagnetics We start with Maxwell's Equations:

/ × H J 0D 0t

C.12.1

/ × E 0B 0t

C.12.2

/#B 0

C.12.3

/#D '

C.12.4

where E = the electric field intensity J = the current density D = the electric flux density (displacement flux) H = the magnetic field intensity B = the magnetic flux density ' = the charge density Assuming linear material properties, these additional relations are also considered: B µH

C.12.5

D E

C.12.6

J )E

C.12.7

where µ = the magnetic permeability = the permittivity ) = the electrical conductivity For the induction heating problem, it is convenient to let the magnetic flux density be represented by the PAGE C - 18



curl of a magnetic vector potential, B / × A

C.12.8

Therefore, Equation C.12.3 is automatically satisfied. Also, we will ignore the displacement flux, D = 0, so Equation C.12.4 is satisfied. Considering Equations C.12.2 and C.12.8, if E /

1 0A 0t

, then

/ × E / × /1 / × 0A / × 0A 0t 0t

C.12.9

thus satisfying Equation C.12.2. Equation C.12.1 is all that remains to be satisfied. Substituting Equations C.12.5 and C.12.8,

/×

1 ( / × A) µ

) / 1 ) 0A J0 e j 7 t ) 0A 0t 0t

C.12.10

Assuming that A = A0 e j7t with the same frequency as the driving current, then 1 ( / × A0 ) µ

/×

J0 ) j7 A0

C.12.11

Expanding the left hand side and assuming that the magnetic permeability is constant within an element yields,

/×

1 ( / × A0 ) µ

1 / ( / # A0 ) 1 / 2 A0) / 1 × ( / × A0) µ

µ

µ

1 / 2 A0 µ

C.12.12

Therefore, the final equation used to determine magnetic potential is, 1 2 / A0 µ

) j 7A0

J0 0

C.12.13



This is solved numerically as three systems of equations in the X, Y, and Z directions, with real and imaginary components. Other quantities of interest can be derived from the magnetic vector potential: Magnetic field, B / × A Eddy current, Je )j7 A Lorentz force, Fl Je × B 1 )72 A 2 Eddy heating, Q e

2 Section 13: Stress Analysis Governing equations

div

)b

)#n

0

t¯

u u¯

where

6 on ) on u

C.13.1

c

C.13.2

in

) = the stress tensor b = the body forces n = the surface unit normal = the surface traction Å = the prescribed displacements

Thermal-Mechanical Contact Mechanical constraint:

g (u) 0

t N (u) n # ) # n 0

on

t N (u) g (u) 0

where

g = the interface gap tN = the normal surface traction

= the contact surface Modification of interface heat transfer coefficient

h 1. /

Variational Formulation PAGE C - 20


1 g h0 kair

C.13.3


) # grad ( u) d 6 6

b # u d6 6

P

<

! g (u) k

¯t # u d

)

P

P

C.13.4

> n # u d 0

c

P

where

k + 1 = k + ! g(u) the augmented Lagrangian multiplier ! = the penalty number

x = ½ (x + x )

Finite Element Discretization B T ) d 6 N T b d 6 N T ¯t d 6

6

)

k 1N T n d

c

0

C.13.5

Linearization of this equation yields: B TD B d 6 6

B 6

T

)nd 6

!N

N T bd 6 6

T s Ns

n

u n 1

N T ¯t d 6

un1 u n

N k

T n s

C.13.6

un 1

where D** = the consistent tangent matrix described later.



Stress Calculation Elastic

)

D (

T )

1 / u ( / u)T 2

T (T) I T

C.13.7

C.13.8

C.13.9

where D = the elasticity matrix containing material properties (Young's modulus, E, and Poisson ratio, ) = the thermal expansion parameter T = the temperature change Inelastic

e p T )

D (

p )

C.13.10

C.13.11

Flow rule

p 0f 0) where

PAGE C - 22

the plastic flow parameter


C.13.12


General Form

1 ( f )

C.13.13

Yield Function ( Von Mises )

f ( ),T, ) F ( ) )

F())

(¯ p,

T) 0

C.13.14

3 (s : s )1/2 2

C.13.15

1 (tr)) I 3

C.13.16

where the deviatoric stress is given by

s

)

Linear hardening rule

H(T) ¯ p Y0 (T )

C.13.17

where H is the linear hardening parameter, Y0 is the initial yield stress, and the effective plastic strain is given by t

¯ p

2 3

p d -

C.13.18

0



Power law hardening rule

( 0 ¯ p ) m

C.13.19

where 0 is the initial yield strain given by

0

E

1 m 1

C.13.20

is a strength parameter and m is the hardening exponent Plasticity

1(f) f 0

C.13.21

Visco-plasticity

1

1(f)

C.13.22

where, 1/ is the viscosity and

1 (f )

f

N

C.13.23

or

1 (f )

PAGE C - 24


M

e

f

1

C.13.24


Radial return mapping algorithm Integrating Equations C.13.11 and C.13.13 by a backward Euler method,

Rn 1

n 1

rn 1

D 1 )n 1

n 1 0f n 1

0)

n 1 t 1 ( f n 1 )

0

C.13.25

0

C.13.26

Solving by Newton-Raphson yields the system of simultaneous equations,

0f 0)

D

t d1 df

0f 0)

T

j

A

)

( )

j

R

j

C.13.27

r

where D D 1

A

2 i 0 f2 0)

C.13.28

p t d1 0p 0¯ df 0 ¯ 0( )

C.13.29

The total stress is then updated by,

) jn11 ) jn 1 ) j

C.13.30

Finally, the consistent tangent matrix in Equation C.13.6 can be derived from Equation C.13.27, D D D

0f 0)

0f 0)

T

D T A

0f 0)

T

D

0f 0)

1

C.13.31

Section 14: Preconditioned Conjugate Gradient Solver APPENDICES, PAGE C - 25


The conjugate gradient method is a semi-direct scheme for finding the solution to the positive definite, symmetric system Ax = b. It does this by building up the solution in steps by the linear combination of a set of independent, A-conjugate basis vectors pi, called search vectors. Thus

x i x0

1 p1 2 p2

...

i pi

C.14.1

A-conjugate means that the inner product (pi, Apj) = 0, I g j . The term "semi-direct" refers to the finite termination property, i.e., that the method is guaranteed to converge to the exact solution in N steps in the absence of numerical round-off, where N is the degree of the matrix A. If the conjugate gradient method actually took that many steps, it would not be competitive with Gaussian elimination solvers. Its utility derives from the fact that a sufficiently accurate solution may be obtained in far fewer steps. In other words, it can be used as an iterative solver. This is particularly important for the large, sparse equation systems that occur in finite element analyses. CPU savings of up to 50% over direct solvers are possible. A complete development of the conjugate gradient method is rather lengthy, but we will provide a summary of how the unconditioned scheme works for the sake of completeness. An initial guess, x0, is chosen either from the initial condition or the result of the previous time step. The initial residual is computed and used as the beginning search vector.

r0 b Ax0 p1 r0

C.14.2

For steps i = 1, ... N-1:

i

( ri 1 , ri 1 ) ( pi , Api )

C.14.3

The formula for i is derived from the minimization of the functional

1(xi )

1 ( xi , Axi ) ( b T xi ) 2

with respect to i. This is equivalent to finding the value of the search vectors available so far.

xi xi 1 i pi ri ri 1 i Api

PAGE C - 26


C.14.4

which minimizes the residual error, given C.14.5


These last two steps are the improvement in the estimate of the solution vector xi and the reduction in the residual error ri. At this point, the norm of the residual error, (ri, ri), is calculated and compared with the convergence criterion . If (ri, ri) > , continue in the loop.

i

( r i ,r i ) ( ri 1 , ri 1 )

pi 1 ri

( ri , Api ) (pi , Api )

C.14.6

i pi

In the calculation of i, the first form is used in practice, but the second is perhaps more indicative of its function. The next search vector is chosen so that it will be A-orthogonal to the previous vector, and thereby to all prior ones. The direction of the new search vector is that of the latest residual with all components aligned with previous search vectors subtracted out. ( ri 1 , ri 1 ) ( r i , r i )

C.14.7

End of loop. When viewed as an iterative technique, the rate of convergence of the conjugate gradient method is governed by the condition number of the matrix A. The condition number is the ratio of the maximum eigenvalue to the minimum. Thus, if A is the identity matrix, the condition number would be one, and the CG solver would converge in one step. The goal of preconditioning is to transform the matrix system so that the new coefficient matrix has a condition number close to one. A conditioning matrix P is chosen such that

P T P M 1 A 1

C.14.8

Pre and post-multiplying the system Ax = b by P, ( PAP T ) Pb Cy d

C.14.9

C PAP T y P T d Pb

C.14.10

where



Since C is similar to PTPA = M-1A, it has the same condition number. So if M-1 A-1, then C I, the identity matrix. When the conjugate gradient method is applied to the transformed system Cy = d and then all the equations restated in terms of the original system, some simplification occurs by defining a new vector zi,

zi P T Pri M 1ri Mzi ri

C.14.11

So it is necessary to find a matrix M which approximates A, but is faster to invert. There are many possibilities, but one of the best choices appears to be partial Cholesky factorization.

M LTDL

C.14.12

The sparsity pattern of the original matrix A is preserved in the factored matrix L, i.e., there is no fill-in. This speeds up the factorization process and minimizes the storage requirements.

The Preconditioned Conjugate Gradient Algorithm can now be outlined: As before, chose x0 and calculate r0 = b - Ax0 Factor A into M = LTDL Solve for z0 from Mz0 = r0 Set search direction p1 = z0 For i = 1, ... N-1; ( zi 1 , ri 1 ) ( pi , Api ) xi xi 1 i pi ri ri 1 i Api zi M 1 ri

i

(C.14.13)

If (zi, ri) > , continue in the loop

i

( zi , ri ) ( zi 1 , ri 1 )

pi 1 zi i pi ( zi 1 , ri 1 ) ( zi , ri )

End of loop

PAGE C - 28


(C.14.14)


Notice that the solution of Mzi = ri takes place in each step. Therefore, each step takes considerably longer than the unconditioned conjugate gradient algorithm. This is more than made up for by the reduction in the number of steps required to reach convergence, typically by a factor of ten. Section 15: Preconditioned Conjugate Residual Solver The Preconditioned Conjugate Residual Solver is used when the system matrix is not symmetric. It is similar to the ICCG method, but a LU decomposition is performed instead of Cholesky. The procedure follows the following steps: Chose an initial estimate x0 and calculate r0 = b - Ax0 Factor A into M = LU Set search direction p1 = r0 For i = 1, ... N-1;

i

( ri 1 , Api ) ( Api , Api )

i pi i Api

xi xi 1 r i ri 1

(C.15.1)

zi M 1 ri

If (ri, ri) > , continue in the loop

i

( Azi , Api ) ( Api , Api )

pi 1 zi

(C.15.2)

i pi

End of loop



Section 16: Micromodeling Equiaxed Dendrite Model This model is also based on instantaneous nucleation, whereby the final grain size is known from the nucleation model. This model is also based on 1--D spherical growth. Following nucleation, the dendrite tip growth is controlled by the supersaturation at the dendrite tip. This means that the tip growth is based on the total undercooling at the tip. As the tip grows, the solid fraction in each grain is not known from the tip position. In fact, the fraction solid is less than the fraction of the grain obtained from the tip position. At each time, the new tip concentration and fraction solid are known from a thermal and solute balance at the scale of the grain. The tip growth velocity is obtained from the Lipton-Glicksman-Kurz model, which simulates the growth of an isolated dendrite tip. The tip continues to grow until it reaches the end of the grain. At this point, solid fraction is still grain envelope less than unity. However, mixing of the solute is complete at this stage. Therefore, a Scheil type Final Grain Size equation can be used to calculate solid fraction. If the phase diagram has a terminal reaction, e.g., eutectic, the remaining liquid gets rapidly transformed into a solid structure.

Figure C-1 shows an eutectic grain and its solute concentration profiles. fs is the fraction solid in the grain and if the dendrite is compressed to form a solid sphere, then the corresponding radius of the solid would be Rs. f g is the fraction of grain enveloped by the dendrite tip. The radius of the grain corresponding to f g is given by Rg. The final grain radius is Rl, which is obtained from the nucleation model.

C* C0 Concentration 1

0

2

fs

3

fg

1

Fraction of Grain Figure C-1 Schematic representation of an equiaxed dendrite grain; region 1 = solid phase; region 2 = interdendritic liquid; region 3 = liquid.

In this figure, it may be noted that there is a boundary layer of solute ahead of the dendrite tip. It is assumed that mixing of solute in the interdendritic region is complete (region 2 in Figure C-1). It is also assumed that the temperature of the grain is uniform and curvature undercooling is neglected. Also it is considered that the thermal undercooling is negligible. The growth of the dendrite tip is controlled mainly by solute diffusion. Therefore, only solutal undercooling is considered.

PAGE C - 30



A solute balance at the scale of the grain is written as: fs

1

kc

(f s)df s

c

( fg fs )

c ( f, t)df c0

P

P

0

fg

C.16.1

where, k is the partition coefficient, c*( f s) is the tip concentration as a function of fs, co is the initial solute concentration, c( f, t ) is the concentration in the liquid region 3 as a function of fraction of grain and time. The three terms are for solute content in the three regions of Figure C-1. The following equation describes a thermal balance at the scale of the grain, assuming that the temperature in the grain is uniform:

'Cp

dT dt

'L df # dt

4 3

% Rl3

Qext # 4%Rl2

C.16.2

where, ' is the density, Cp is the specific heat, L is the gravimetric latent heat of fusion, Qext is the external heat flux of the solidifying grain. The assumption of uniform temperature and interface equilibrium leads to the following equation: dT

dT m dc dt dt dt

C.16.3

where, T* is the temperature at the dendrite tip and m is the slope of the liquidus line. The incorporation of the thermal balance equation in the solute balance equation leads to the following quadratic equation in the dendrite tip concentration, c*:

Ac 2 Bc C 0

C.16.4

where, the coefficients A, B, and C are evaluated at every time step. The coefficients A, B, C involve terms that include total solute content in the solid ( region 1 ) and the total solute content in the liquid (region 3). In order to calculate the total solute content in the liquid region of the grain as well as to obtain the concentration at the end of the grain, the diffusion equation in the liquid region needs to be solved. This is done by assuming that the diffusion is quasi-steady in nature. Then, the diffusion equation is solved analytically with the following boundary condition:

r Rg ,

c c

C.16.5



Solution of the above quadratic equation leads to the evaluation of interface concentration at the dendrite tip at each time step. Once the interface concentration is known, the rate of change of fraction of solid at each time step is obtained from the thermal balance equation as given above. This is used to calculate the heat source term in the energy balance equation at every time step. The tip growth velocity is obtained with the Lipton-Glicksman-Kurz model which considers that growth of the dendrite tip is controlled by solute diffusion and that thermal undercooling is neglected. This is mostly valid for a situation where the Peclet number is low. The following equation results from this model:

d Rg dt

A T2

C.16.6

where T is the solutal undercooling at the dendrite tip and A is a parameter that involves solute diffusivity in the liquid, liquidus slope, initial solute concentration, Gibbs-Thompson coefficient and the partition coefficient. Since nucleation starts instantaneously with zero degree undercooling, the interface concentration will increase to drive the dendrite tip growth. The growth of the dendrite tip is rapid in the beginning because the driving force i.e., the difference between the interface concentration and concentration at the end of the grain, is large. Toward the end of solidification both the interface concentration and the concentration at the end of grain increase because of solute rejection in liquid, and hence the growth rate is slowed down. The solute diffusion calculation is continued until the time when the dendrite tip radius becomes equal to the grain radius. The equiaxed dendritic growth continues until the fraction of solid becomes one or another terminal reaction takes place. If this reaction is an eutectic reaction, all the remaining liquid gets transformed into an eutectic structure.

PAGE C - 32



The secondary dendrite arm spacing parameter is obtained using the coarsening model of Feurer and Wunderlin, which is described through the following equation:

2

M # ts

1/3

C.16.7

where 2 is secondary dendrite arm spacing, ts is the local solidification time, M is the coarsening rate constant which can be computed with the following equation:

D ln M

where

Cl

m

C0

C.16.8

m(1 k)(C0 Cl ) m

= Gibbs-Thompson Coefficient D = Solute Diffusion Coefficient in Liquid Phase Co= Initial Solute Concentration of the alloy m = Liquidus slope k = solute partition coefficient Clm = final composition of solute in liquid at the end of dendrite solidification

In most cases, Clm is equal to the eutectic composition, Ce. A typical value of M for an Al-7%Si alloy is 8.8. 10-6 m . s-1/3 Coupled Eutectic Growth Models The Coupled Eutectic Growth Models are divided into two categories: 1. Instantaneous Nucleation 2. Continuous Nucleation These models can be applicable to both regular and irregular eutectics. In the case of regular eutectics, growth of both phases of the eutectic structure are non-faceted in nature. For irregular eutectic, the growth process of one of the phases is faceted. Growth of the faceting phase requires considerably higher entropy of fusion. Examples of faceted growth are graphite growth in stable austenite/graphite eutectic and Silicon in Al-Si eutectic. The metastable austenite/cementite eutectic is an example of non-faceted/non-faceted type eutectic growth. Growth of both the stable and metastable eutectic are addressed here. Growth of the stable eutectic usually proceeds at a higher temperature. For example, the difference between the stable and metastable eutectic temperature in cast iron is about 6 (C. This value may, however, be influenced by the amount of alloying elements present. A higher cooling rate results in the formation of a metastable eutectic. These models assume bulk heterogeneous nucleation at foreign sites which are already present within melt or intentionally added to the melt by inoculation. So these models are valid for the equiaxed region of castings. The basic theory of heterogeneous nucleation has been described by Turnbull and Fisher. Considering the fact that the initial nucleation site density n0 in the melt will decrease as the nucleation APPENDICES, PAGE C - 33


proceeds ( i.e., extinction of nucleation sites ), the nucleation rate is given as:

n K1 [n0 n(t) ] exp

K2

T ( T )2

C.16.9

where K1 is proportional to the collision frequency of the atoms of the melt with the nucleation sites of the heterogeneous particles and K2 is described as a function of the interfacial energy balance between the nucleus, the liquid, and the foreign substrates, (t) is the nucleation density as a function of time. The drawback of the above model is that the final grain density does not depend on solidification conditions, which is an experimental fact. To avert this, the instantaneous nucleation model is modified to take into account the dependance of cooling rate on the number of nucleation sites or substrates. With an increase in cooling rate or undercooling, the number of substrates increases which explains the existence of more grains in faster cooled regions of a casting. The continuous nucleation model is based in principle on Oldfield's approach, as modified by Rappaz. The modifications lie in the use of a statistical approach. This model is described in Figure C-2.

Figure C-2 Continuous Distribution of Nucleation Sites used for modeling equiaxed solidification

PAGE C - 34



In continuous nucleation, the process starts at the nucleation temperature and proceeds until the stage when the minimum in the cooling curve is attained. The grains which have already nucleated grow to some extent by the time the minimum undercooling is reached, giving a Gaussian distribution in size. By Liquid Eutectic cells conducting a few experiments, the mean and standard deviation of this distribution can easily be determined from simple DTA-type experiments using liquid from a given melt. Regardless of the nucleation process, the models assume that the grains are equiaxed and that they grow freely in liquid as spheres until they impinge on each other. The growth process stops when all the liquid is consumed. Figure C-3 is a schematic representation of equiaxed growth of eutectic grains at some intermediate stage of growth. The growth of the grains is controlled by thermal undercooling at the solid/liquid interface. Solutal undercooling is neglected here since solute diffusion during eutectic solidification is negligible. The Figure C-3 Schematic representation of thermal undercooling is given by the difference between the eutectic equiaxed eutectic growth model. temperature and the actual solid/liquid interface temperature. The bulk temperature at the grain is known from the macromodel. The difference between the eutectic temperature and this temperature gives bulk undercooling. The interfacial undercooling is obtained from the bulk undercooling from a heat balance equation This is possible once the final grain size is known from the nucleation law. The growth velocity of eutectic grains is given by the following equation, where growth is assumed to take place by screw dislocation:

dRe dt

µ T2

C.16.10

where µ is the growth constant. Both the stable and metastable eutectics are assumed to grow according to the above equation. During growth, the partition of solute element between the solid and the liquid phase is accounted for. The stable eutectic temperature is computed at each time by considering the actual solute concentration in the liquid, as shown below:

T e T e m( C e C e ) 1

1

C.16.11

where Te and Ce are the equilibrium eutectic temperature and composition respectively. Te1 and Ce1 are the eutectic temperatures and composition respectively at a given time step.



The rate of change of the fraction of solid is calculated with the Johnson-Mehl approximation, assuming that the solid/liquid interface is weighted by the factor ( 1 -- f s ) to take into account the impingement of grains toward the later part of solidification:

dR 0 fs

(1 fs ) 4 % Re2 N e dt 0t

C.16.12

where Re is the radius of eutectic grain and N is the substrate density. When the instantaneous nucleation model is used, N becomes a function of cooling rate. For continuous nucleation, N becomes a function of temperature. Ductile Iron Eutectic Model The eutectic growth process in ductile iron is a divorced growth of austenite and graphite, which do not grow concomitantly. At the beginning of the liquid/solid transformation, graphite nodules nucleate in the liquid and grow in the liquid to a small extent, about 10 µm. The formation of graphite nodules and their limited growth in liquid depletes the melt locally of carbon in the vicinity of the nodules. This facilitates the nucleation of austenite around the nodules, forming a shell. Further growth of these nodules is possible by diffusion of carbon from the melt through the austenite shell.

Liquid Austenite Graphite

Cl Ca Cc

Mathematical simulation of this growth begins with an R R R instantaneous nucleation model that determines the final Radius Temperature grain size from the local cooling rate at the onset of solidification. Second, once the austenite shell is formed Figure C-4 Schematic representation of an eutectic ductile iron grain and associated concentration profiles around each nodule, the diffusion equation for carbon and phase diagram. equiaxed eutectic growth model. through the austenitic shell is solved in 1--D spherical coordinates. The boundary conditions are known from the phase diagram because thermodynamic equilibrium is maintained locally. Conservation of mass and solute is maintained in each grain. Because of the density variation resulting from the growth of austenite and graphite, the expansion/contraction of the grain is taken into account by allowing the final grain size to vary. Toward the end of solidification, the grains impinge on each other. This is taken into consideration by using the Johnson-Mehl approximation. C

PAGE C - 36


a

l


Figure C-4 shows a schematic representation of an eutectic ductile iron grain. This is the situation after the graphite nodules grow in liquid to a limited extent following nucleation. Using a spherical coordinate system, a mass balance is written as:

'c. 4 % Rc3 'a. 4 % 3

3

(R a R c ) 3

3

'l . 4 % ( Rl3 3

Ra3 ) mav

C.16.13

where 'c, 'a, 'l are the densities of graphite, austenite, and liquid respectively Rc, Ra, Rl are radii of graphite, austenite, and final grain respectively mav is average mass of the grain Assuming complete mixing of solute in liquid, the overall solute balance is written as:

'c.1. 4 3

%

Ra

Rc3

Rc

'a.c(r,

t) 4 % r 2 dr

'l cl . 4 % (Rl3 3

Ra3 ) cav

C.16.14

Differentiation of the above two equations and use of Ficks' law in spherical coordinates leads to two equations for graphite and austenite growth rates following some manipulation. This diffusion equation is solved for the austenite shell with the following two boundary conditions: 1. at r = Rc, c(r,t) = cc 2. at r = Ra, c(r,t) = ca where cc, ca are obtained from the phase diagram for temperature T as shown in Figure C-4. The liquid concentration at this temperature is given as cl at temperature = T. cc, ca, cl are obtained from phase diagram as shown in Figure C-4.



During solidification, the densities of the different phases are computed according to the following equations:

'l

'a

l 1

0.1201 12.67.10 6 T 9.0.10 4 w c 2.16.10 3 wSi l

a2

0.1193 9.7.10 6 T 4.0.10 3 w c 2.2.10 4 w c a

'c

1.3.10 3 wSia

1 0.4419 10.5.10 6 T

C.16.15

1

C.16.16

C.16.17

where densities are given in cgs units and temperature in (K,

w c wt % of carbon in liquid l

w c wt % of carbon in austenite a

w Si wt % of silicon in liquid l

w Si wt % of silicon in austenite a

The average density of a ductile iron grain is given by:

'av 'l ( 1

fs )

's fs

C.16.18

where

's

4 3

% Rc3 'c

4 % (Ra3 Rc3 ) 'a 3 4 % Ra3 3

C.16.19

The densities are updated at each time based on the temperature. The rate of change of fraction of solid is obtained with the following equation, which incorporates the Johnson-Mehl approximation for grain impingement:

0 fs 0 Ra

( 1 fs ) 4 % Ra2 N 0t 0t The source term in the energy equation is computed using the above equation.

PAGE C - 38


C.16.20


Gray/White Iron Eutectic Model This model is a special case of coupled eutectic growth model and is applicable to cast iron only. In cast iron, one may obtain both gray and white iron depending on the melt composition and cooling conditions. Given a controlled melt composition, the most important factor that will determine whether a given region will solidify as white or gray is the cooling rate. It has been observed that for a specific melt composition and solidification condition, there exists a parameter called a critical cooling rate. If a region of a casting solidifies with a cooling rate higher than the critical cooling rate, then it will be white. The reverse is the case for gray iron. The white structure is brittle and in most gray iron castings, it is considered to be deleterious. This model differs from the Coupled Eutectic Growth Models previously described in that the nucleation is described by a predetermined continuous distribution function. The nucleation rate equations for both gray and white iron are obtained from the following equation:

N A ( T )n

C.16.21

where N is the final eutectic cell density. By experiment, it was found that A = 7.12 nuclei/cm3/K2 and n = 2. Differentiation of the above equation with respect to time leads to the following expression for the nucleation rate:

dN

n A ( T )n 1 dT dt dt

C.16.22

The expression for growth rates was put forward by Oldfield, Magnin, and Kurz. The growth rate equation follows an expression similar to Oldfield's nucleation rate equation. Using a spherical grain approximation, the growth rate expression is given by:

dRe dt

B ( T )m

C.16.23

For gray iron, as reported by Magnin and Kurz, B is taken to be 38.7e-7 cm/s/K2 and m as 2. The interfacial undercooling is T. For white iron, the value of B is taken from the work by Hillert to be 30.0e-6 cm/s/K2. It is apparent that white iron grows at a much faster rate than gray iron, which is also an experimental fact. Appropriate expressions for nucleation and growth rates are used in the following statistical approach.



Statistical Nucleation Model: The distribution of nuclei are assumed to be described by a polynomial. The treatment in this section follows recent work by Dantzig and coworkers. The nature of the polynomial is shown in Figure C-5 and expressed by the following equation:

(r)

A1 A2 r A3 r 2

C.16.24

where (r) describes the cell density as a function of cell radius, r and A1, A2, A3 are constants to be determined from the properties of the distribution. Figure C-5 shows the distribution. The three unknown parameters in the above equation are obtained with the following three properties (Figure C-5 ): 1. At the maximum radius, R, the cell density is zero. 2. The first derivative of the distribution evaluated at the maximum radius is zero. 3. The area under the shaded area in Figure C-5, which is the total number of cells in the distribution, is N.

Figure C-5 Eutectic cell distribution assumed for gray/white iron.

The following three equations describe these properties mathematically:

(R)

0

C.16.25

dn

r R 0 dr

R

R0

PAGE C - 40


( r ) dr

N

C.16.26

C.16.27


Since the nuclei are assumed to be spherical, the fraction of solid can be locally expressed as: R

4 3

fs

% r 3.(r).dr

C.16.28

R0

After manipulation with the properties, an expression for the fraction of solid is obtained. Differentiation of this expression leads to another expression that involves the nucleation rate and growth rate of nuclei. The nucleation rates and growth rates for gray and white iron eutectic cells are obtained using equations expressed earlier. To take into account impingement, the growth rate expressions are modified by the use of Johnson-Mehl expression. Finally, the source term in the energy equation is obtained from the time rate of change of fraction of solid. Ductile Iron Eutectoid Model This model may be used during the eutectoid transformation while describing the complete phase transformation of ductile iron from pouring temperature to room temperature. Also it may be used when the iron is heated from room temperature to the austenitizing temperature and then annealed or normalized as part of a heat treatment procedure. The eutectoid reaction leads to the decomposition of austenite into ferrite and graphite for the case of the stable eutectoid and to pearlite for the metastable eutectoid transformation. Usually, the metastable eutectoid temperature is lower than the stable eutectoid temperature. Slower cooling rates result in more stable eutectoid structure. Following solidification, the solubility of carbon in Figure C-6 Schematic Representation of Eutectoid portion austenite decreases with the drop in temperature until the of Fe-C-Si phase diagram. stable eutectoid temperature, AT is reached (Figure C-6). The rejected carbon migrates toward graphite nodules, which are the carbon sink. This results in carbon depleted regions in austenite around the graphite nodules. This provides favorable sites for ferrites to nucleate, which grow as a shell around graphite nodules. If the complete transformation of austenite is not achieved when the metastable temperature, A1 in Figure C-6 is reached, pearlite forms and grows in competition with ferrite.



Growth of Ferrite: Even though ferrite can form either from the breakdown of pearlite or from the direct decomposition of austenite, it is assumed here that ferrite results only from the latter source. The following assumptions are made for modeling the growth of ferrite: 1. 2. 3. 4.

The austenite to ferrite transformation occurs at steady state and is controlled by carbon diffusion. The ferrite grains grow as spherical shells within austenite grains and the number of ferrite grains is equal to the number of graphite nodules. Thermodynamic equilibrium exists at graphite/ferrite and ferrite/austenite interfaces. These are defined by equilibrium solvus lines extended below the equilibrium eutectoid temperatures. Diffusion from the ferrite/austenite interface towards austenite is neglected as diffusion coefficients and concentration gradients in austenite are small compared to those in ferrite.

Austenite (A) Ferrite (F) Graphite (G)

CG CF/A

CA

CA/F CG/F

RC

RF

Ra

Radius Figure C-7 Schematic representation of the ferrite growth model.

PAGE C - 42


Figure C-8 Eutectoid region of a binary Fe-C phase diagram.


Solution of the diffusion equation of carbon in ferrite with the flux balance at the ferrite/austenite interface leads to the following equation (see Figure C-7):

dRF dt

Rc ' F Dc R F (R F 'F

C A /F C G/F R c ) C F /A C A /F

C.16.29

where

DcF = RF = Rc = G/F F/A C , C , CA/F =

the carbon diffusion coefficient in ferrite the radius of the ferrite grain and graphite nodule the radius of the graphite nodule carbon concentration in ferrite at the graphite/ferrite interface, carbon concentration in ferrite at the ferrite/austenite interface, and carbon concentration in austenite at the ferrite/austenite interface respectively (Figure C-7).

Since the rejected carbon migrates to the graphite nodule, concomitant growth of ferrite and graphite results. The following equation derives from mass conservation:

'c 4 % 3

(RC dRc )3 Rc CG

3

'F 4 % 3

(RF dRF )3 RF C A/F 3

C.16.30

Therefore, knowing the radius of the ferrite grain, the radius of the graphite nodule can be obtained from the above equation. Then the rate of change of fraction of ferrite grain is obtained by:

df F dt

(1 fF fP ) 4 % N RF2

dRF dt

C.16.31

where f F, f P are fractions of ferrite and pearlite, and N is the number of graphite nodules. The above equation is used to obtain the source term due to ferrite growth associated with the stable eutectoid transformation. Nucleation and Growth of Pearlite: The nucleation of pearlite usually occurs at austenite grain boundaries. It has been demonstrated that pearlite colonies grow either as spheres or hemispheres following nucleation. By the movement of high mobility ( i.e., low interface energy ) incoherent interfaces, these colonies can grow edgewise or sidewise into the austenite. This means that pearlite grows in competition with ferrite until austenite is completely transformed.



Transformation of austenite into pearlite is usually modeled with an Avrami equation because the study of nucleation of pearlite is difficult, especially under continuous cooling conditions. Also, pearlite grains impinge on each other at an early stage, especially at a relatively high cooling rate. Here, equations for nucleation and growth of pearlite grains are taken from the work of Mehl and Dube:

dNpearl dt

dRpearl dt

5.07.106exp 370

C.16.32

0.0168 exp 94.8

C.16.33

Teud

Teud

where the pearlite nucleation density is given in nuclei/mm3/sec and the undercooling is given in (K. The nucleation process stops once the minimum in the cooling curve is reached. The expression for the time rate of change of fraction of pearlite transformed is given by an expression similar to that for ferrite. Gray Iron Eutectoid Model The gray iron eutectoid transformation model is based on the approach used for gray iron eutectic. Here a statistical distribution is assumed. Details of this approach are given above in the explanation for the gray iron eutectic model. Nucleation and growth of ferrite takes place once the temperature drops below the stable eutectoid temperature. If the transformation of austenite is not complete when the metastable eutectoid temperature is reached, then nucleation and growth of pearlite takes place. In this statistical approach, nucleation and growth takes place once the temperature drops below the transformation temperature. During nucleation, the radii of nuclei are introduced at R0 (Figure C-5). Since the existing nuclei grow, both the cell density and maximum radii, R, increase, while the minimum radius, R0, stays the same. When nucleation ends at the minimum point of the cooling curve, the existing nuclei keep on growing until the transformed fraction becomes 1. The number of nuclei does not change from this point on. An instantaneous nucleation mechanism was used for ferrite. The growth of ferrite grains is controlled by a diffusion mechanism as explained for the growth of the ductile iron eutectoid. The expression for growth rate is given below:

dRferr dt

C2 C3 C4 C3

F

Dc 2

RF

1 1 0 RF RF

C.16.34

The above expression is derived by using a solute flux balance at the ferrite/austenite interface along PAGE C - 44



with the diffusion equation, where RF0 = the radius of ferrite nucleus C2 = the carbon content in the middle of ferrite grain C3 = the carbon content at the ferrite/austenite interface C4 = the carbon content in austenite The nucleation and growth rate expressions for pearlite are the same as those for the ductile iron eutectoid model. These equations have been suggested by Mehl and Dube. All of the above equations are solved as a linear system by the use of Gauss elimination. The rate of change of fraction of pearlite and ferrite transformed are used to calculate the source term in the macroscopic energy equation at each time step. Peritectic Transformation Model In a peritectic transformation, liquid reacts with an existing solid phase to form a new solid phase. In conventional models, the new solid is assumed to form at the interface between the parent liquid and solid phases. Once the new solid phase is formed, further reaction between the parent phases is limited by the layer of solid formed. Hence the rate of reaction is controlled by the diffusion of solute through the shell of the transformed product. The following discussion is for the Fe-C system. However, it is valid for all other systems undergoing a peritectic transformation, with a few relevant assumptions. It has been suggested by some researchers that the peritectic transformation may be achieved through a liquid layer in between the parent and the product solid phases. This mechanism has been adopted in the present model. For example, in the case of steel, the austenite phase forms initially at the root of the dendrite arms of the delta phase and grows along the delta/liquid interface. The speed of this growth is the same as that with which liquid moves toward the delta phase. The diffusion problem can be simplified as the liquid layer is very thin and the diffusion of carbon in the liquid is very rapid so that the carbon concentration gradient in the liquid is negligible. Here the solute diffusion boundary layer is much greater than the system size i.e., the following condition holds:

c

where

2 Dl

V

L

C.16.35

c =

the thickness of the boundary layer Dl = the solute diffusivity in liquid V = the speed of growth L = the system size



It is assumed that the above condition is maintained for any system undergoing peritectic transformation. The model is based on a Brody-Flemings formulation, with recent modifications suggested by Zou and Tseng. For the peritectic transformation given by the reaction,

L

C.16.36

the following mass balance equation may be written:

[ ( f L.CL Cs, ) ( f L.Cl f Cs, ) ] df s (1 f s ) dCl

s, 2L

dCs,

s, 2L

dCs,

C.16.37

where

f L and f fractions of liquid and delta phases reacting Cl the liquid concentration

Cs, and Cs, solute concentrations at the delta/liquid and austenite/liquid interfaces respectively L the system size dCl the change solute concentration in liquid

s, and s, the solute boundary layer thicknesses in gamma and delta phases After some mathematical manipulation, an expression is obtained that relates the solute concentration in liquid with the fraction of solid transformed, involving some parameters such as dimensionless coefficients for back diffusion for both delta and austenite phases i.e., and . According to the Brody-Flemings model, the case of = 0.5 does not correspond to the physical characteristics of equilibrium solidification. In that case, should approach infinity. Therefore, a modified back diffusion parameter, 1 has been proposed by Clyne and Kurz. The basis of this calculation is that, in the original Brody-Flemings treatment for high values, solute was not conserved in the system. According to Clyne and Kurz, the modified back diffusion parameter is defined as:

1

1 exp

1

1 exp 1 2

2

C.16.38

Differentiation of the equation involving fraction transformed and solute concentration in liquid leads to the expression for rate of change of fraction of solid assuming thermodynamic equilibrium at the solid/liquid interface, which is used to calculate the source term in the energy equation.

PAGE C - 46



Solid Transformation Models This model is only applicable to the Fe-C system and is used for tracking the fraction transformed for the cases of delta to gamma, gamma to ferrite, and gamma to cementite. A hypoeutectoid steel may form some delta phase in the beginning while the remaining liquid and some delta phase undergo a peritectic transformation to form some gamma phase. The remaining delta phase gets transformed to gamma phase. This transformation is addressed by the present model. Delta to gamma transformation will be active in the appropriate temperature range when the wt% carbon equivalent value is less than 0.17%. The delta to gamma phase transformations can be described by the Johnson-Mehl equation, also known as Avrami equation:

f v 1 exp [ k(T) t n ]

C.16.39

where f v = the fraction transformed f v = the fraction transformed k(T) = the rate constant The rate constant is a function of nucleation and growth rates. It depends on the transformation temperature and is related to the shape and position of the C curve in a TTT ( time-temperature-transformation ) diagram. In most cases, this curve has a parabolic shape and can be approximated as:

k (T ) exp ( aT 2 bT c )

C.16.40

where T represents temperature in K. The parameters a, b, c, n have been determined for each of these transformations. Appropriate values are chosen for this transformation from the literature. Differentiation of the equation for fraction transformed with respect to time leads to the expression for the time rate of change of fraction of delta transformed to gamma. Again, prior to reaching the eutectoid temperature, some of the austenite phase may transform into alpha phase as part of a pro-eutectoid transformation. If you started with a hypereutectoid composition, the pro-eutectoid transformation will be from austenite ( gamma ) to cementite. Both of these pro-eutectoid transformations are addressed by the current model. The wt% carbon equivalent determines whether the gamma to ferrite or gamma to cementite transformation will be used. Both of these models require that the equiaxed dendrite model be chosen for the initial liquid/solid phase transformation.



The radius of the transformed ferrite or cementite grain is obtained with the following equation:

Tp

R

1

T

V (T ) dT

C.16.41

T

where

T = cooling rate V(T) = the growth velocity of the ferrite or cementite grain Assuming steady state thickening, the growth velocity at a given temperature is:

V

2 D C C0 ) 2x (C0 C)

C.16.42

where D = the diffusivity of carbon in austenite C = the concentration in austenite at ferrite/austenite interface C = the concentration in ferrite at ferrite/austenite interface Co = the original solute concentration in the alloy x = the radius of ferrite Fraction of austenite transformed into ferrite is given as:

f

2 R d

C.16.43

where f = the fraction transformed d = the austenite grain size Similar equations have been used for the gamma to cementite transformation, where the growth velocity equation and associated data are obtained from published literature.

PAGE C - 48



Scheil Model The Scheil model makes the assumptions of complete mixing of solute in liquid and no solute diffusion in the solid phase. The following equation describes the differential form of the Scheil equation:

(cl cs ) df s (1 f s ) dcl

C.16.44

where

cl the liquid composition at the solid/liquid interface

cs the solid composition at the solid/liquid interface dcl the change in concentration in liquid f s the fraction of solid

Consider a portion of a binary phase diagram as shown in Figure C-9.

Tm

Tl T Ts

Cs Co

Cl

Solute Concentration

Figure C-9 A portion of a binary phase diagram.

In Figure C-9, Tl and Ts are the liquidus and solidus temperatures respectively. cl and cs are solute concentrations in the liquid and solid phases at some temperature, T. co is the initial solute concentration in the alloy and Tm is the melting point of the pure solvent. The change of fraction of solid obtained with the above equation is used for the calculation of the source term in the macroscopic energy equation.



Output of Micromodels Equiaxed Dendrite Model This primary dendrite solidification yields the following spatially varying output: 1. 2. 3. 4. 5.

DENDRITE RADIUS DENDRITE TIP COMPOSITION PRIMARY FRACTION OF SOLID PRIMARY INT. SOLID FRACTION SECONDARY DENDRITE ARM SPACING

The DENDRITE RADIUS provides the current position of the dendrite tip and volume fraction of the dendritic grain as it varies with time. At the end of the primary solidification, this parameter will equal the final grain radius as calculated from the instantaneous nucleation law with the prevailing cooling rate value. This is true provided a terminal reaction such as an eutectic reaction does not take place beforehand. Subtraction of the value of the PRIMARY FRACTION OF SOLID at the beginning of the eutectic reaction provides the total amount of the eutectic at a given location. The PRIMARY INT. SOLID FRACTION parameter increases from a small value to unity as the primary solidification proceeds. It is the ratio of the current volume of the grain as known from the DENDRITE RADIUS and the final volume of the grain as known from the nucleation law. At the onset of the eutectic reaction, subtraction of the value of the PRIMARY INT. SOLID FRACTION from unity provides the amount of the fraction of the eutectic between the grains. Subtraction of this amount of eutectic between grains from the total amount of the eutectic provides the amount of eutectic between dendrite arms. In most cases, it is important to know how much eutectic will form between grains and between dendrite arms. With the progress of solidification, the DENDRITE TIP COMPOSITION parameter will continuously change from the initial to the eutectic composition. A map of this parameter over the entire casting at a given instant gives an idea about microsegregation, since the concentration of the solid phase forming is proportional to the tip concentration. The information about microsegregation is important for describing non-equilibrium behavior in castings. This is the cause of interdendritic precipitation of eutectic, even if the initial alloy composition is not on eutectic tie line. The SECONDARY DENDRITE ARM SPACING (SDAS), which is the spacing between the secondary arms of a dendrite, depends upon the local solidification time. As the SDAS increases, the mechanical properties deteriorate. SDAS also determines the spacing of precipitates and/or porosity. The Secondary Dendrite Arm Spacing is output when either the eutectic transformation model and/or the peritectic transformation model are used. Coupled Eutectic Growth Model with Instantaneous Nucleation 1. 2. 3. 4. 5.

LARGE EUT. GRAIN RADIUS EUTECTIC FRACTION OF SOLID INTER-LAMELLAR SPACING METASTABLE EUT. GRAIN RAD. MET. EUTECTIC FR. OF SOLID

The LARGE EUT. GRAIN RADIUS and METASTABLE EUT. GRAIN RAD. parameters provide the PAGE C - 50



instantaneous value of the stable and metastable eutectic grain radii, which can be used to control the mechanical properties of the cast part. The EUTECTIC FRACTION OF SOLID and MET. EUTECTIC FR. OF SOLID parameters give the relative amount of stable and metastable eutectic structure. For example, in cast iron the metastable eutectic (white) may be undesirable. The INTER-LAMELLAR SPACING parameter determines the fineness of the eutectic. Smaller values of this parameter provide better mechanical properties. The Jackson-Hunt equation for the eutectic interlamellar spacing is given with the following equation:

2 V

K

C.16.45

Where, V is the velocity at the eutectic front. The velocity of the eutectic front can be expressed in the following form:

V µ ( T )2

C.16.46

Here, T is the interfacial undercooling at the eutectic front. Combining the above two equations, the following equation is written:

Vt t Vt t 2

2t t

C.16.47

The instantaneous value of the inter-lamellar spacing is obtained with the above equation. At the end of solidification, an average value of the inter-lamellar spacing is obtained. Coupled Eutectic Growth Model with Continuous Nucleation The following parameters are similar to those for the Coupled Eutectic Growth Model with Instantaneous Nucleation. The only additional quantity is the EUTECTIC GRAIN RADIUS, which gives the stable eutectic grain density as a function of time over the entire casting. In many cases, a large number of this parameter will be desirable from the standpoint of mechanical properties. 1. 2. 3. 4. 5. 6.

LARGE EUT. GRAIN RADIUS EUTECTIC FRACTION OF SOLID EUTECTIC GRAIN RADIUS INTER LAMELLAR SPACING METASTABLE EUT. GRAIN RAD. MET. EUTECTIC FR. OF SOLID



Ductile Iron Eutectic Model The following parameters are displayed when this particular micromodel is selected. 1. AUSTENITE RADIUS 2. GRAPHITE RADIUS 3. EUTECTIC FRACTION OF SOLID 4. EUTECTIC GRAIN RADIUS The EUTECTIC GRAIN RADIUS parameter gives the final radius of eutectic grains over the entire casting. This is governed by the function used to describe the dependence of the nodule count on the cooling rate. In ductile iron, each eutectic grain consists of a graphite nodule enveloped in an austenite shell. The AUSTENITE RADIUS and GRAPHITE RADIUS provide the instantaneous values of the solidified grain size and nodule size respectively. At the end of solidification, they provide a correct description of the final grain size and nodule size. The AUSTENITE RADIUS should in principle coincide with the final grain size as given by the EUTECTIC GRAIN RADIUS parameter. However, because of the grain impingement, AUSTENITE RADIUS may exceed the EUTECTIC GRAIN RADIUS. A map of the EUTECTIC FRACTION OF SOLID parameter can be used to determine areas of shrinkage formation in castings. AUSTENITE RADIUS AND GRAPHITE RADIUS can be related to the mechanical properties of castings. Density is calculated from the local fraction of graphite, austenite, and liquid, thus capturing the peculiar contraction and expansion behavior of ductile iron. Gray/White Iron Eutectic Model This model uses a statistical distribution for nucleation. 1. LARGE EUT. GRAIN RADIUS 2. SMALL EUT. GRAIN RADIUS 3. FRACTION OF SOLID 4. EUTECTIC GRAIN RADIUS 5. INTER LAMELLAR SPACING 6. METASTABLE EUT. GRAIN RAD. 7. SMALL MET. EUT. GR. RADIUS 8. MET. EUTECTIC FR. OF SOLID 9. MET. EUTECTIC GR. DENSITY The LARGE EUT. GRAIN RADIUS and SMALL EUT. GRAIN RADIUS refer to the maximum and minimum values of the stable (gray) eutectic grain radius as a function of time during eutectic growth. Similarly, METASTABLE EUT. GRAIN RAD. and SMALL MET. EUT. GR. RADIUS parameters are relevant for the metastable (white) eutectic. Mechanical properties of the cast part are a function of the stable and metastable eutectic grain sizes. FRACTION OF SOLID gives the amount of the gray eutectic, whereas MET. EUTECTIC FR. OF SOLID gives the amount of the white eutectic. In most cases, the gray structure is more desirable as it gives improved tensile strength and ductility. The EUTECTIC GRAIN RADIUS parameter gives the gray eutectic grain density and the MET. EUTECTIC GRAIN DENSITY gives white eutectic grain density. These two parameters are connected to mechanical properties in a similar fashion to the grain radius parameters. The Eutectic Grain Density of Gray and White Iron are used to describe the number of grains per unit volume at a given location of a casting. This can be correlated with the mechanical properties of the cast part. The INTER LAMELLAR SPACING parameter calculates the spacing of the gray eutectic which is explained under Coupled Eutectic Growth Model with Instantaneous Nucleation. Ductile Iron Eutectoid Model PAGE C - 52



As explained earlier, the stable eutectoid growth refers to the decomposition of austenite into ferrite and graphite and the metastable eutectoid growth refers to the decomposition of austenite into pearlite, which is a coupled growth of ferrite and cementite. 1. 2. 3. 4. 5.

LARGE FERRITE GR. RADIUS FRACTION OF FERRITE FRACTION OF PEARLITE LARGE PEARLITE GR. RADIUS LOCAL PEARLITE GRAIN DENSITY

The properties of the iron depend strongly on the relative amounts of ferrite and pearlite in the matrix. As the pearlite content increases, tensile and yield strengths also increase, but at the cost of ductility. Ferrite content controls fracture toughness and dynamic properties of iron. The amount of ferrite increases as the nodule count of the iron increases. The FRACTION OF FERRITE and FRACTION OF PEARLITE give the relative amount of stable and metastable eutectoid structures. The pearlite/ferrite ratio can be related to tensile strength through its effect on matrix microhardness. The LARGE FERRITE GR. RADIUS and LARGE PEARLITE GR. RADIUS provide the stable and metastable eutectoid grain radii as a function of time. LARGE PEARLITE GR. RADIUS can provide a qualitative estimate of interlamellar spacing, which can be related to mechanical properties. Also, LOCAL PEARLITE GRAIN DENSITY can be used to estimate the mechanical properties. Usually, a finer pearlite grain size is associated with a finer interlamellar spacing with better mechanical properties. Gray Iron Eutectoid Model This model uses a statistical distribution of nuclei as explained for Eutectic Gray/White Iron model. 1. 2. 3. 4. 5. 6. 7.

LARGE FERRITE GR. RADIUS SMALL FERRITE GR. RADIUS LARGE PEARLITE GR. RADIUS SMALL PEARLITE GR. RADIUS FRACTION OF FERRITE FRACTION OF PEARLITE LOCAL PEARLITE GRAIN DENSITY

The above parameters reflect the same kind of behavior as they do in the case of the Ductile Iron Eutectoid Model. The only difference is that stable and metastable eutectoid grain sizes are provided as a range extending from a minimum value to a maximum value.



Peritectic Transformation Model 1. 2.

PERITECTIC FR. OF SOLID LIQUID CONCENTRATION

Usually, peritectic growth is limited by the formation of the solid transformed product at the reacting liquid/solid phase boundary. The PERITECTIC FR. OF SOLID parameter gives the volume fraction of solid resulting from this reaction. It is important to know the amount of the phase formed through this reaction, as it usually forms as a surface layer on the primary dendritic solid phase. Segregation of solute is a problem during this reaction, as diffusion is limited in the transformed phase. LIQUID CONCENTRATION provides a measure of this effect as a function of time. Segregation is a problem unless the cast part undergoes significant plastic deformation and heat treatment later on. Solid Transformation Models 1. 2.

FRACTION TRANSFORMED FRAC. OF PROEUTECTOID PHASE

The FRACTION TRANSFORMED parameter refers to the delta to gamma phase transformation. The FRAC. OF PROEUTECTOID PHASE refers to the fraction of proeutectoid ferrite or cementite formed from the austenite phase as a function of time. The carbon equivalent value controls which type of the proeutectoid phase (ferrite or cementite) will form. Scheil Model The Scheil Model is usually used to model the primary dendrite growth. 1. 2.

PRIMARY FRACTION OF SOLID LIQUID CONCENTRATION

The PRIMARY FRACTION OF SOLID parameter provides the time-dependent evolution of the primary solid fraction. The LIQUID CONCENTRATION parameter gives the progressive concentration in the liquid at the solid/liquid interface of the solidifying grain. This is also the concentration in the entire liquid phase of the grain since the Scheil model assumes complete solute mixing in liquid. Since the effect of the undercooling at the tip is not taken into consideration, this model will not predict any variation in primary solid fraction as a function of cooling rate as one observes in an equiaxed dendrite model.

PAGE C - 54



Interlamellar spacing The interlamellar spacing that is addressed here is based on the Jackson-Hunt model of eutectic growth. It is assumed that the interlamellar spacing follows the extremum criterion condition, which means that such interlamellar spacing will be chosen by the system so as to minimize the undercooling at the eutectic front. In other words, it is assumed that the growth valocity is maximized for the extremum condition. It may be mentioned here that the Jackson-Hunt theory is valid under steady state growth conditions. In castings, the growth process is unsteady except during the eutectic plateau of the cooling curve. The growth process during eutectic arrest is close to steady state growth. Therefore, Figure C-10 while viewing the contours of this parameter over the casting, you should be in the steady state growth range. Toward the end of eutectic solidification, the growth rate is rapidly increased. Therefore, the interlamellar spacing calculated at that time may not be representative of the actual spacing. The expression for the Jackson-Hunt theory of eutectic growth is given by the following equation:

2ex V

where

Kr Kc

C.16.48

ex =

the interlamellar spacing based on the extremum condition V = the growth velocity of the eutectic front



The expressions for the parameters Kr and Kc are obtained from the following, assuming that the eutectic structure is composed of and phases:

m ¯ C1 P1 f (1 f ) D

Kc

C.16.49

and

Kr 2 m ¯

sin () fm

sin ()

(1 f ) m

C.16.50

where

m ¯

P1

m m

m m

1 M

n

3

%

3

sin 2 (n % f)

C.16.51

C.16.52

where

m and m = absolute liquidus slopes in and side of the phase diagram

and =

f= C1 = D= and =

Gibbs-Thompson coefficients associated with and phases respectively the volume fraction of the phase the difference in composition between the ends of the eutectic tie line the diffusion coefficient in liquid the angles are the angles subtended by the tangents of and interfaces with the line OY at the intersection of and interfaces (see Figure C-10).

The equation of interlamellar spacing is rewritten as:

ex

PAGE C - 56


(Kr / Kc)

V

C.16.53


The Jackson-Hunt Parameter here refers to the value of Kr/Kc. Typical experimental values for this parameter for different systems are listed below:

Eutectic Systems

Kr/Kc(mm3s-1)

Ag-Pb

1.2. 10-7

Ag3Sn-Sn

2.8.10-7

Al-Al2Cu

1.2. 10-7--1.4. 10-7 (function of C0)

Al-Si

5.8. 10-7--3.1. 10-6 (function of G)

Al-Zn

6.4. 10-8

Bi-Zn

6.9. 10-8

Cd-Pb

2.1. 10-8

Cd-Sn

7.2. 10-8

Cd-Zn

2.8. 10-8

Fe-C

5.6. 10-6

Pb-Sn

2.8. 10-8--3.3. 10-8

Sn-Zn

6.9. 10-8

Section 17: Cooling Curve Analysis If the internal thermal gradients in a sample are negligible (i.e., if the temperature in the sample is uniform), then the following heat balance equation may be written for the solidifying sample-mold system: Heat transferred to mold = Heat generated by phase transformation --- Heat lost by metal Mathematically, this is expressed with the following equation:

dQ L dt

' V Cp dT hA( T To ) dt

(C.17.1)

where QL = latent heat of phase transformation ' = density of metal Cp = Specific heat of metal T = metal temperature t = time h = heat transfer coefficient A = surface area V = volume of sample To = ambient temperature



The above equation is rearranged as:

dT dt

dQ L

( ' V Cp )

hA( T T0 )

dt

cc

(C.17.2)

This equation is valid for the cooling curve. If there is no phase transformation during cooling of metal, dQ L then is zero. Therefore, the following equation is written: dT

dT dt

hA(T T0 )

( ' V Cp )

(C.17.3)

zc

Here, the subscript zc represents the zero curve. Taking the difference between these two equations, the following equation is written:

dQ L dt

' V Cp

dT dt

dT cc

dt

(C.17.4) zc

Integration of this equation yields: tf

QL

' VCp

dT dt

dT cc

dt

dt

(C.17.5)

zc

o

Here, tf is the solidification time. Therefore, the latent heat for phase transformation is obtained as L = QL/'V.

PAGE C - 58


PREFIXD.DAT FILE FORMAT

APPENDIX D prefixd.dat FILE FORMAT The formatted file containing the description of the problem is the prefixd.dat file. This file is normally created by PreCAST and processed by DataCAST to check for errors in the model and then create the binary simulation file. It is possible to create the prefixd.dat file manually if the problem is small. However, it is much more likely that you would want to make minor changes in the problem setup, such as changing one heat transfer coefficient, by editing the prefixd.dat file. This appendix provides a description of the records and record formats in this file. Each record of the prefixd.dat file is identified by the two labels LA and LB. These two numbers must be in 2I2 format. If there are any units in the record, they must be in the format given. Everything else can be in free format. ( 1, 0 ) Data Set - Title statements Input: Format: Content:

Note:

LA, LB, TITLE 2I2, A80 LA =1 LB =0 TITLE = Arbitrary line of information for run documentation Up to three records of this type may be included.

( 1, 1 ) Data Set - Number of nodes and elements Input: Format: Content:

LA, LB, NTNOD, NTEL 2I2, 1X, 2I10 LA =1 LB =1 NTNOD = Total number of nodes NTEL = Total number of elements

( 2, 0 ) Data Set - Control parameters Input: Format: Content:

LA, LB, THERMAL, FREE_SURFACE, TWO_D 2I2, 1X, 3I5 LA =2 LB =0 THERMAL = 0 for no thermal solution ( flow only ) = 1 for thermal solution FREE_SURFACE = 0 for no free surface flow = 1 for free surface flow ( filling transients ) TWO_D = 0 for 3D geometry = 1 for 2D Cartesion geometry = 2 for 2D cylindrical geometry

APPENDICES, PAGE D - 1


(3, 0 ) Data Set - Solid element information Input: Format: Content:

LA, LB, IEL, ITYPE, MINDEX, NODE1, ... NODE10 2I2, 1X, 3I5, 10I7 LA =3 LB =0 IEL = Element number ITYPE = 1 for 8-node brick element = 2 for 4-node tetrahedral element = 3 for 6-node wedge element = 6 for 4-node quadrilateral element = 7 for 3-node triangular element = 9 for 2-node bar element = 10 for 10-node tetrahedral element N = Material ID number, points to Data Set ( 3, 1 ) NODE1, = Connectivity data ...NODE*

( 3, 1 ) Data Set - Solid element additional information Input: Format: Content:

Note:

PAGE D - 2

LA, LB, U1, N, MTYPE, FLUID, FILLED, VINDEX, THETA, TIC, UPDATE, MOLD, STRESS 2I2, 1X, I1, 4X, 5I3, 2E15.0, 3I5 LA =3 LB =1 U1 = Units for initial condition temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine N = Material ID number MTYPE = Material number in Data Set ( 5, 0 ) FLUID = 0 this material does not flow = 1 normal flow material = 2 filter material = 3 foam material FILLED = 0 if elements with this index are initially empty = 1 if elements with this index are initially filled VINDEX = Pointer to Data Set ( 6, 5 ) for moving solid elements THETA = Implicit-explicit time stepping parameter TIC = Temperature initial condition for elements with this index UPDATE = Frequency at which to reintegrate the element matrices for this ID MOLD = 0 if this ID does not represent a mold = 1 if this ID represents a mold This is only used when running multiple cycles with the parameters TCYCLE and NCYCLE.. STRESS = 0 no stress calculation for this material = 1 linear elastic material = 2 plastic, linear hardening material = 3 plastic, power law hardening material = 4 viscoplastic 1, linear hardening material = 5 viscoplastic 1, power law hardening material = 6 viscoplastic 2, linear hardening material = 7 viscoplastic 2, power law hardening material The FLUID parameter should be 0 for 1D elements



( 3, 2 ) Data Set - 1D Conduction element information Input: Format: Content:

LA, LB, U1, IEL, INDEX, NODE1, NODE2, AREA 2I2, 1X, I1, 4X, 2I5, 2I7, E15.0 LA =3 LB =2 U1 = Units for the cross-sectional area = 1 for meters**2 = 2 for centimeters**2 = 3 for millimeters**2 = 4 for feet**2 = 5 for inches**2 IEL = Element number INDEX = Pointer to Data Set ( 3, 1 ) NODE1, = Connectivity data NODE2 AREA = Cross-sectional area

( 3, 3 ) Data Set - 1D Interface element information Input: Format: Content:

LA, LB, U1, IEL, INDEX, NODE1, NODE2, AREA 2I2, 1X, I1, 4X, 2I5, 2I7, E15.0 LA =3 LB =3 U1 = Units for the cross-sectional area = 1 for meters**2 = 2 for centimeters**2 = 3 for millimeters**2 = 4 for feet**2 = 5 for inches**2 IEL = Element number INDEX = Pointer to Data Set ( 6, 3 ) NODE1, = Connectivity data NODE2 AREA = Cross-sectional area

( 4, 0 ) Data Set - Node coordinates Input: Format: Content:

LA, LB, U1, NODE, X, Y, Z 2I2, 1X, I1, 4X, I5, 3E15.0 LA =4 LB =0 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches NODE = Node number X,Y,Z = Cartesian coordinates of NODE



( 4, 1 ) Data Set - Enclosure node coordinates Input: Format: Content:

LA, LB, U1, NODE, X, Y, Z 2I2, 1X, I1, 4X, I5, 3E15.0 LA =4 LB =1 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches NODE = Enclosure node number X,Y,Z = Cartesian coordinates of NODE

( 4, 2 ) Data Set - Radial symmetry information Input: Format: Content:

Note:

LA, LB, U1, NSS, NAXIS, X, Y, Z 2I2, 1X, I1, 4X, 2I5, 3E15.0 LA =4 LB =2 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches =1) NSS = Number of symmetric structures ( default NAXIS = 1 for first point defining the axis of symmetry = 2 for second point defining the axis of symmetry X,Y,Z = Cartesian coordinates of NAXIS Two records of this type are required if the radial symmetry option is being used.

( 4, 3 ) Data Set - Mirror symmetry information Input: Format: Content:

Note:

PAGE D - 4

LA, LB, U1, NPLANE, X, Y, Z 2I2, 1X, I1, 4X, I5, 3E15.0 LA =4 LB =3 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches NPLANE = 1 for first point defining plane of symmetry = 2 for second point defining plane of symmetry = 3 for third point defining plane of symmetry X,Y,Z = Cartesian coordinates of NPLANE Three records of this type are required if the mirror symmetry option is being used



( 4, 4 ) Data Set - Gravitational acceleration vector Input: Format: Content:

LA, LB, U1, AX, AY, AZ 2I2, 1X, I1, 4X, I5, 3E15.0 LA =4 LB =4 U1 = Units for acceleration = 1 for m / sec**2 = 2 for cm / sec**2 = 3 for mm / sec**2 = 4 for ft / sec**2 = 5 for in / sec**2 AX = X component of gravity AY = Y component of gravity AZ = Z component of gravity

( 4, 5 ) Data Set - Gravitational vector rotation Input: Format: Content:

LA, LB, U1, TIME, X1, Y1, Z1, X2, Y2, Z2 2I2, 1X, I1, 4X, I5, 6E10.0 LA =4 LB =5 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches TIME = Time function number X1,Y1,Z1 = Coordinates for first point of rotation axis X2,Y2,Z2 = Coordinates for second point of rotation axis

( 4, 6 ) Data Set - Rotation data for Periodic Boundary Input: Format: Content:

Note:

LA, LB, U1, N, NAXIS, THETA, X, Y, Z 2I2, 1X, I1, 4X,2I5, 4E15.0 LA =4 LB =6 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches N = Periodic data set number NAXIS = 1 for first point defining the axis of rotation = 2 for second point defining the axis of rotation THETA = Angle of rotation X,Y,Z = Cartesian coordinates of NAXIS Two records of this type are required if the periodic boundary involves rotation



( 4, 7 ) Data Set - Translation data for Periodic Boundary Input: Format: Content:

LA, LB, U1, N, DX, DY, DZ 2I2, 1X, I1, 4X, I5, 3E15.0 LA =4 LB =7 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches N = Periodic data set number DX = Translation in X direction DY = Translation in Y direction DZ = Translation in Z direction

( 4, 8 ) Data Set - Centrifugal data Input: Format: Content:

Note:

LA, LB, U1, U2, NAXIS, TIME, OMEGA, X, Y, Z 2I2, 1X, 2I1, 3X, 2I5, 4E15.0 LA =4 LB =8 U1 = Units of the coordinates = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches U2 = Units for angular velocity = 1 for radians / second = 2 for radians / minute NAXIS = 1 for first point defining the axis of rotation = 2 for second point defining the axis of rotation TIME = Time function number for angular velocity OMEGA = Constant angular velocity X,Y,Z = Cartesian coordinates of NAXIS Two records of this type are required if the centrifugal option is being used.

( 5, 0 ) Data Set - Material properties Input: Format: Content:

PAGE D - 6

LA, LB, INDEX, NAME, IENTH 2I2, 1X, A30, I5 LA =5 LB =0 INDEX = Corresponds to MTYPE in Data Set ( 3, 1 ) NAME = Material name IENTH = Enthalpy curve index, corresponds to set ( 5, 5 )



( 5, 1 ) Data Set - Density Information Input: Format: Content:

LA, LB, U1, MAT, ITEMP, RHO 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB =1 U1 = Units for density = 1 for kg / m**3 = 2 for g / cm**3 = 3 for g / mm**3 = 4 for lb / ft**3 = 5 for lb / in**3 MAT = Material number ITEMP = Temperature function index for RHO RHO = Baseline or constant density

( 5, 2 ) Data Set - Specific Heat / Enthalpy Information Input: Format: Content:

LA, LB, U1, MAT, ITEMP, CP 2I2, 1X, I1, 4X, 3I5, E15.0 LA =5 LB =2 U1 = Units for specific heat = 1 for kJ / kg / K = 2 for cal / g / C = 3 for Btu / lb / F MAT = Material number ITEMP = Temperature function index for CP CP = Constant specific heat

( 5, 3 ) Data Set - Conductivity Information Input: Format: Content:

Note:

LA, LB, U1, MAT, ITEMP, COND, ANISO 2I2, 1X, I1, 4X, 2I5, E15.0, E15.0 LA =5 LB =3 U1 = Units for thermal conductivity = 1 for W / m / K = 2 for cal / cm / C / sec = 3 for cal / mm / C / sec = 4 for Btu / ft / F / sec = 5 for Btu / in / F / sec = 6 for cal / cm / C / min = 7 for Btu / ft / F / min = 8 for Btu / in / F / min MAT = Material number ITEMP = Temperature function index for COND COND = Baseline or constant conductivity ANISO = anisotropic multiplier which is applied in the t parametric direction for 8 noded brick elements and 6 noded wedge elements. In the case of a 4 noded quadralaterial element, the anisotropic multiplier is applied in the s parametric direction. The ANISO parameter is optional.



( 5, 4 ) Data Set - Viscosity Information Input: Format: Content:

LA, LB, U1, MAT, ITEMP, VIS 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB =4 U1 = Units for viscosity = 1 for Pascal - sec = 2 for N - sec / m**2 = 3 for centpoise = 4 for poise = 5 for lb / sec / ft = 6 for lb / min / ft = 7 for lb / hr / ft MAT = Material number ITEMP = Temperature function index for VIS VIS = Baseline or constant viscosity for newtonian flow

( 5, 5 ) Data Set - Enthalpy curves Input: Format: Content:

LA, LB, U1, U2, CURVE, POINT, TEMP, VALUE 2I2, 1X, 2I1, 3X, 2I5, 2E15.0 LA =5 LB =5 U1 = Units for temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine U2 = Units for enthalpy = 1 for kJ / kg = 2 for cal / g = 3 Btu / lb CURVE = Corresponds to IENTH in Data Set ( 5, 0 ) POINT = Number of point on the curve TEMP = Temperature of point VALUE = Enthalpy value of point

( 5, 6 ) Data Set - Fraction Solid and Latent Heat Input: Format: Content:

PAGE D - 8

LA, LB, U1, MAT, ITEMP, LHEAT 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB =6 U1 = Units for latent heat = 1 for kJ / kg = 2 for cal / g = 3 Btu / lb MAT = Material number ITEMP = Temperature function index for fraction solid LHEAT = Latent heat



( 5, 7 ) Data Set - Liquidus and Solidus Temperatures Input: Format: Content:

LA, LB, U1, U2, MAT, LIQUID, SOLID 2I2, 1X, I1, 4X, I5, 2E15.0 LA =5 LB =7 U1,U2 = Units for temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine MAT = Material number LIQUID = Liquidus temperature SOLID = Solidus temperature

( 5, 8 ) Data Set - Mold Permeability Input: Format: Content:

LA, LB, U1, MAT, PERM 2I2, 1X, I1, 4X, I5, E15.0 LA =5 LB =8 U1 = Units for permeability = 1 for meters**2 = 2 for centimeters**2 = 3 for millimeters**2 = 4 for feet**2 = 5 for inches**2 MAT = Material number ( points to 5 0 card ) PERM = Permeability

( 5, 9 ) Data Set - Surface Tension Information Input: Format: Content:

LA, LB, U1, MAT, ITEMP, ST 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB =9 U1 = Units for surface tension = 1 for N / m = 2 for dyne / cm = 3 for lb / ft = 4 for lb / in MAT = Material number ( points to 5 0 card ) ITEMP = Temperature function index for ST ST = Baseline or constant surface tension



( 5, 10 ) Data Set - Transformation Temperature Input: Format: Content:

LA, LB, U1, INDEX, ICOOL, TT 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 10 U1 = Units for transformation temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine INDEX = Reference index for Data Sets ( 5, 16 ) to ( 5, 24 ) ICOOL = Cooling rate function index TT = Constant transformation temperature

( 5, 11 ) Data Set - Partition Coefficient Input: Format: Content:

LA, LB, INDEX, ITEMP, PC 2I2, 1X, 5X, 2I5, E15.0 LA =5 LB = 11 INDEX = Reference index for Data Sets ( 5, 16 ) to ( 5, 24 ) ITEMP = Temperature function index PC = Baseline or constant partition coefficient

( 5, 12 ) Data Set - Solute Diffusivity Input: Format: Content:

PAGE D - 10

LA, LB, U1, INDEX, ITEMP, DIFF 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 12 U1 = Units for diffusivity = 1 for m**2 / sec = 2 for cm**2 / sec = 3 for mm**2 / sec = 4 for ft**2 / sec = 5 for in**2 / sec = 6 for m**2 / min = 7 for cm**2 / min = 8 for mm**2 / min = 9 for ft**2 / min = 10 for in**2 / min INDEX = Reference index for Data Sets ( 5, 16 ) to ( 5, 24 ) ITEMP = Temperature function index DIFF = Baseline or constant solute diffusivity



( 5, 13 ) Data Set - Liquidus Slope Input: Format: Content:

LA, LB, U1, INDEX, ICONC, LS 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 13 U1 = Units for liquidus slope = 1 for K / wt% = 2 for C / wt% = 3 for F / wt% = 4 for R / wt% INDEX = Reference index for Data Sets ( 5, 16 ) to ( 5, 24 ) ICONC = Concentration function index LS = Baseline or constant liquidus slope

( 5, 14 ) Data Set - Substrate Density, Nodule Count Input: Format: Content:

LA, LB, U1, INDEX, IFUNC 2I2, 1X, I1, 4X, 2I5 LA =5 LB = 14 U1 = Units for substrate density = 1 for 1 / m**3 = 2 for 1 / cm**3 = 3 for 1 / mm**3 = 4 for 1 / ft**3 = 5 for 1 / in**3 INDEX = Reference index for Data Sets ( 5, 16 ) to ( 5, 24 ) IFUNC = Cooling rate function index if a positive number, for instantaneous nucleation = Temperature function index if a negative number, for continuous nucleation

( 5, 15 ) Data Set - Lamellar Spacing Input: Format: Content:

LA, LB, U1, INDEX, ICOOL 2I2, 1X, I1, 4X, 2I5 LA =5 LB = 15 U1 = Units for lamellar spacing = 1 for m = 2 for cm = 3 for mm = 4 for ft = 5 for in INDEX = Reference index for Data Sets ( 5, 16 ) to ( 5, 24 ) ICOOL = Cooling rate function index



( 5, 16 ) Data Set - Equiaxed Dendrite Micromodel Input: LA, LB, U1, MAT, I1, I2, I3, I4, I5, GT, C0 Format: 2I2, 1X, I1, 4X, 6I5, 2E15.0 Content: LA =5 LB = 16 U1 = Units for Gibbs-Thompson coefficient = 1 for m * K = 2 for cm * K = 3 for mm * K = 4 for ft * F = 5 for in * F MAT = Material number I1 = Index to Data Set ( 5, 10 ) I2 = Index to Data Set ( 5, 11 ) I3 = Index to Data Set ( 5, 12 ) I4 = Index to Data Set ( 5, 13 ) I5 = Index to Data Set ( 5, 14 ) GT = Gibbs-Thompson coefficient C0 = Initial alloy composition ( 5, 17 ) Data Set - Coupled/Metastable Eutectic Growth Micromodel Instantaneous or Continuous Nucleation Input: LA, LB, U1, U2, U3, MAT, I1, I2, I3, I4, GC, MGC, SMP, CCR, EC Format: 2I2, 1X, 3I1, 2X, 5I5, 5E15.0 Content: LA =5 LB = 17 U1 = Units for growth constants = 1 for m / sec / K**2 = 2 for cm / sec / K**2 = 3 for mm / sec / K**2 = 4 for ft / sec / F**2 = 5 for in / sec / F**2 = 6 for m / min / K**2 = 7 for cm / min / K**2 = 8 for mm / min / K**2 = 9 for ft / min / F**2 = 10 for in / min / F**2 U2 = Units of temperature for solvent melting point = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine U3 = Units for critical cooling rate for transition = 1 for K / sec = 2 for C / sec = 3 for F / sec = 4 for R / sec = 5 for K / min = 6 for C / min = 7 for F / min = 8 for R / min MAT = Material number I1 = Index to Data Set ( 5, 10 ) I2 = Index to Data Set ( 5, 11 ) I3 = Index to Data Set ( 5, 14 ) I4 = Index to Data Set ( 5, 15 ) GC = Stable growth constant MGC = Metastable growth constant SMP = Solvent melting point CCR = Critical cooling rate for transition PAGE D - 12



EC

= Eutectic composition

( 5, 18 ) Data Set - Eutectic Ductile Iron Micromodel Input: LA, LB, MAT, I1, I2 Format: 2I2, 1X, 5X, 3I5 Content: LA =5 LB = 18 MAT = Material number I1 = Index to Data Set ( 5, 10 ) I2 = Index to Data Set ( 5, 14 ) ( 5, 19 ) Data Set - Eutectoid Ductile Iron Micromodel Input: Format: Content:

LA, LB, MAT, I1, I2 2I2, 1X, 5X, 3I5 LA LB MAT I1 I2

=5 = 19 = Material number = Index to Data Set ( 5, 10 ) = Index to Data Set ( 5, 14 )

( 5, 20 ) Data Set - Eutectic Grey/White Iron Micromodel Input: Format: Content:

LA, LB, U1, MAT, I1, CCR 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 20 U1 = Units for critical cooling rate for transition = 1 for K / sec = 2 for C / sec = 3 for F / sec = 4 for R / sec = 5 for K / min = 6 for C / min = 7 for F / min = 8 for R / min MAT = Material number I1 = Index to Data Set ( 5, 10 ) CCR = Critical cooling rate for grey to white transition

( 5, 21 ) Data Set - Eutectoid Grey Iron Micromodel Input: Format: Content:

LA, LB, MAT, I1 2I2, 1X, 5X, 2I5 LA LB MAT I1

=5 = 21 = Material number = Index to Data Set ( 5, 10 )



( 5, 22 ) Data Set - Peritectic Transformation Micromodel Input: LA, LB, U1, MAT, I1, I2, I3, I4, I5, I6, I7, GT, C0, EC, RFS Format: 2I2, 1X, I1, 4X, 8I5, 4E15.0 Content: LA =5 LB = 22 U1 = Units for Gibbs-Thompson coefficient = 1 for m * K = 2 for cm * K = 3 for mm * K = 4 for ft * F = 5 for in * F MAT = Material number I1 = Index to Data Set ( 5, 10 ) I2 = Index to Data Set ( 5, 11 ) for solid forming partition coefficient I3 = Index to Data Set ( 5, 11 ) for solid reacting partition coefficient I4 = Index to Data Set ( 5, 12 ) for liquid diffusivity I5 = Index to Data Set ( 5, 12 ) for solid forming diffusivity I6 = Index to Data Set ( 5, 12 ) for solid reacting diffusivity I7 = Index to Data Set ( 5, 13 ) GT = Gibbs-Thompson coefficient C0 = Alloy composition EC = Eutectic composition RFS = Reacting solid fraction ( 5, 23 ) Data Set - Solid State Transformation Micromodels Input: LA, LB, MAT, CO Format: 2I2, 1X, 5X, I5, E15.0 Content: LA =5 LB = 23 MAT = Material number CO = Alloy composition ( 5, 24 ) Data Set - Scheil Micromodel Input: LA, LB, U1, U2, MAT, I1, I2, I3, FT, SMP, C0 Format: 2I2, 1X, 2I1, 3X, 4I5, 3E15.0 Content: LA =5 LB = 24 U1 = Units for final temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine U2 = Units of temperature for solvent melting point = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine MAT = Material number I1 = Index to Data Set ( 5, 10 ) I2 = Index to Data Set ( 5, 11 ) I3 = Index to Data Set ( 5, 13 ) FT = Final temperature SMP = Solvent melting point C0 = Alloy composition ( 5, 40 ) Data Set - Carreau-Yasuda Non-Newtonian Viscosity Input:

PAGE D - 14

LA, LB, U1, U2, U3, MAT, ITEM0, ITEMI, ITEML, ITEMP, ITEMY, VIS0, VISI, PHASE, POWER, YASUDA



Format: Content:

2I2, 1X, 3I1, 3X, 6I5, 5E15.0 LA =5 LB = 40 U1 = Units for viscosity at zero shear rate = 1 for Pascal - sec = 2 for N - sec / m**2 = 3 for centpoise = 4 for poise = 5 for lb / sec / ft = 6 for lb / min / ft = 7 for lb / hr / ft U2 = Units for viscosity at infinite shear rate = 1 for Pascal - sec = 2 for N - sec / m**2 = 3 for centpoise = 4 for poise = 5 for lb / sec / ft = 6 for lb / min / ft = 7 for lb / hr / ft U3 = Units for time = 1 for sec = 2 for min MAT = Material number ITEM0 = Temperature function index for VIS0 ITEMI = Temperature function index for VISI ITEML = Temperature function index for PHASE ITEMP = Temperature function index for POWER ITEMY = Temperature function index for YASUDA VIS0 = Zero shear rate viscosity VISI = Infinite shear rate viscosity PHASE = Phase shift coefficient POWER = Power law coefficient YASUDA = Yasuda coefficient

( 5, 41 ) Data Set - Filter data Input: Format: Content:

LA, LB, U1, U2, MAT, ITIME, ITEMP, VOIDF, SAREA, HTC 2I2, 1X, 2I1, 3X, 3I5, 3E15.0 LA =5 LB = 41 U1 = Units for specific surface area (area/volume) = 1 for 1 / meters = 2 for 1 / centimeters = 3 for 1 / millimeters = 4 for 1 / feet = 5 for 1 / inches U2 = Units for fluid-filter heat transfer coefficient = 1 for W / m**2 / K = 2 for cal / cm**2 / C / sec = 3 for cal / mm**2 / C / sec = 4 for Btu / ft**2 / F / sec = 5 for Btu / in**2 / F / sec = 6 for cal / cm**2 / C / min = 7 for Btu / ft**2 / F / min = 8 for Btu / in**2 / F / min MAT = Material number ITIME = Time function index for HTC ITEMP = Temperature function index for HTC VOIDF = Void fraction of the filter APPENDICES, PAGE D - 15


SAREA HTC

= specific surface area of the filter = Fluid-filter interfacial heat transfer coefficient

( 5, 50 ) Data Set - Magnetic permeability data Input: Format: Content:

LA, LB, U1, MAT, ITEMP, MAGP 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 50 U1 = Units for magnetic permeability = 1 for Henry / meter = 2 for Henry / centimeter = 3 for Henry / millimeter = 4 for Henry / feet = 5 for Henry / inch MAT = Material number ITEMP = Temperature function index for MAGP MAGP = Baseline or constant magnetic permeability

( 5, 51 ) Data Set - Electrical conductivity data Input: Format: Content:

PAGE D - 16

LA, LB, U1, MAT, ITEMP, ECON 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 51 U1 = Units for electrical conductivity = 1 for 1 / ( ohm-meter ) = 2 for 1 / ( ohm-centimeter ) = 3 for 1 / ( ohm-millimeter ) = 4 for 1 / ( ohm-feet ) = 5 for 1 / ( ohm-inch ) MAT = Material number ITEMP = Temperature function index for ECON ECON = Baseline or constant electrical conductivity



( 5, 60 ) Data Set - Elastic Modulus Input: Format: Content:

LA, LB, U1, MID, ITEMP, ELAST 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 60 U1 = Units for elastic modulus = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 MID = Material id number ITEMP = Temperature function index for ELAST ELAST = Baseline or constant elastic modulus

( 5, 61 ) Data Set - Poisson ratio Input: Format: Content:

LA, LB, MID, ITEMP, POISR 2I2, 1X, 4X, 2I5, E15.0 LA =5 LB = 61 MID = Material id number ITEMP = Temperature function index for POISR POISR = Baseline or constant poisson ratio

( 5, 62 ) Data Set - Thermal expansion coefficient Input: Format: Content:

LA, LB, U1, MID, ITEMP, THEXP 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 62 U1 = Units for thermal expansion coefficient = 1 for 1 / Kelvin = 2 for 1 / Celsius = 3 for 1 / Fahrenheit = 4 for 1 / Rakine MID = Material id number ITEMP = Temperature function index for THEXP THEXP = Baseline or constant thermal expansion coeffient



( 5, 63 ) Data Set - Yield stress Input: Format: Content:

LA, LB, U1, MID, ITEMP, YIELD 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 63 U1 = Units for yield stress = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 MID = Material id number ITEMP = Temperature function index for YIELD YIELD = Baseline or constant yield stress

( 5, 64 ) Data Set - Hardening Parameter Input: Format: Content:

LA, LB, U1, MID, ITEMP, HARD 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 64 U1 = Units for hardening = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 MID = Material id number ITEMP = Temperature function index for HARD HARD = Baseline or constant hardening

( 5, 65 ) Data Set - Hardening exponent Input: Format: Content:

PAGE D - 18

LA, LB, MID, ITEMP, HARDE 2I2, 1X, 4X, 2I5, E15.0 LA =5 LB = 65 MID = Material id number ITEMP = Temperature function index for HARDE HARDE = Baseline or constant hardening exponent



( 5, 66 ) Data Set - Visco power coefficient Input: Format: Content:

LA, LB, MID, ITEMP, VPOW 2I2, 1X, 4X, 2I5, E15.0 LA =5 LB = 66 MID = Material id number ITEMP = Temperature function index for VPOW VPOW = Baseline or constant visco power coefficient

( 5, 67 ) Data Set - Fluidity Input: Format: Content:

LA, LB, U1, MID, ITEMP, FLUID 2I2, 1X, I1, 4X, 2I5, E15.0 LA =5 LB = 67 U1 = Units for fluidity = 1 for 1 / seconds = 2 for 1 / minutes MID = Material id number ITEMP = Temperature function index for FLUID FLUID = Baseline or constant fluidity

( 6, 0 ) Data Set - Neumann boundary conditions, pointer data Input: Format: Content:

LA, LB, IEL, FACE, INDEX, IFLAG 2I2, 1X, 4I5 LA =6 LB =0 IEL = Element number FACE = Element face number ( see Note A ) INDEX = Pointer to Data Set ( 6, 1 ) IFLAG = 1 if face participates in view factor calculations = 0 otherwise or if element is 1D



( 6, 1 ) Data Set - Neumann boundary conditions, supplementary data Input: Format: Content:

LA, LB, U1, U2, U3, INDEX, ITIMQ, ITIMH, ITIME, ITIMT, ITEMH, ITEME, Q, H, EPS, TA 2I2, 1X, 3I1, 2X, 7I3, 4E12.0 LA =6 LB =1 U1 = Units for heat flux = 1 for W / m**2 = 2 for cal / cm**2 / sec = 3 for cal / mm**2 / sec = 4 for Btu / ft**2 / sec = 5 for Btu / in**2 / sec = 6 for cal / cm**2 / min = 7 for Btu / ft**2 / min = 8 for Btu / in**2 / min U2 = Units for heat transfer coefficient = 1 for W / m**2 / K = 2 for cal / cm**2 / C / sec = 3 for cal / mm**2 / C / sec = 4 for Btu / ft**2 / F / sec = 5 for Btu / in**2 / F / sec = 6 for cal / cm**2 / C / min = 7 for Btu / ft**2 / F / min = 8 for Btu / in**2 / F / min U3 = Units for ambient temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine INDEX = Corresponds to INDEX in set ( 6, 0 ) ITIMQ = Time function index for Q ITIMH = Time function index for H ITIME = Time function index for EPS ITIMT = Time function index for TA ITEMH = Temperature function index for H ITEME = Temperature function index for EPS Q = Specified heat flux H = Convection heat transfer coefficient EPS = Epsilon for radiative heat transfer TA = Ambient temperature

( 6, 2 ) Data Set - Coincident node information Input: LA, LB, IEL1, FACE1, IEL2, FACE2, IH Format: 2I2, 1X, I7, I5, I7, 2I5 Content: LA =6 LB =2 IEL1 = Element 1 FACE1 = Coincident face of element 1 ( see Note A ) IEL2 = Element 2 FACE2 = Coincident face of element 2 ( see Note A ) IH = Pointer to Data Set ( 6, 3 ) Note: The temperature of the face of element 1 is used in determining a value from the temperature function.

PAGE D - 20



( 6, 3 ) Data Set - Interface heat transfer coefficients Input: Format: Content:

LA, LB, U1, INDEX, TIME, TEMP, H 2I2, 1X, I1, 4X, 3I5, E15.0 LA =6 L1 =3 U1 = Units for heat transfer coefficient = 1 for W / m**2 / K = 2 for cal / cm**2 / C / sec = 3 for cal / mm**2 / C / sec = 4 for Btu / ft**2 / F / sec = 5 for Btu / in**2 / F / sec = 6 for cal / cm**2 / C / min = 7 for Btu / ft**2 / F / min = 8 for Btu / in**2 / F / min INDEX = Corresponds to IH in Data Set ( 6, 2 ) TIME = Time function number TEMP = Temperature function number H = Value of interface heat transfer coefficient

( 6, 4 ) Data Set - Enclosure faces for view factor radiation model Input: Format: Content:

LA, LB, INDEX1, INDEX2, NODE1, ... NODE4 2I2, 1X, 2I5, 4I7 LA =6 LB =4 INDEX1 = Index of temperature and emissivity data in Data Set ( 6, 6 ) INDEX2 = Index of velocity data in Data Set ( 6, 5 ) NODE1, = Connectivity in bar, triangular, or quadrilateral face ...NODE*

( 6, 5 ) Data Set - Velocity data for moving enclosure faces or solid elements Input: Format: Content:

LA, LB, U1, INDEX, TIME, U, V, W 2I2, 1X, I1, 4X, 2I5, 3E15.0 LA =6 LB =5 U1 = Units for enclosure velocity = 1 for meters / sec = 2 for centimeters /sec = 3 for mm / sec = 4 for feet / sec = 5 for inches / sec = 6 for meters / min = 7 for centimeters /min = 8 for feet / min = 9 for inches / min INDEX = Corresponds to INDEX2 in set ( 6, 4 ) TIME = Time function number U,V,W = X, Y, Z components of velocity



( 6, 6 ) Data Set - Temperature and emissivity data for enclosure faces Input: Format: Content:

LA, LB, U1 , INDEX, TIME, TEMP, FATEM, EPS 2I2, 1X, I1, 4X, 3I5, 2E15.0 LA =6 LB =6 U1 = Units for face temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine INDEX = Corresponds to INDEX1 in set ( 6, 4 ) TIME = Time function number for FATEM TEMP = Temperature function number for EPS FATEM = Face temperature EPS = Emissivity ( epsilon )

( 6, 7 ) Data Set - Multipoint constraints Input: Format: Content:

Note:

LA, LB, SLAVE, M1, W1, M2, W2, M3, W3, M4, W4 2I2, 1X, I5, 4(I5,E12.0) LA =6 LB =7 SLAVE = Number of node which is constrained M1-M4 = Master nodes W1-W4 = Weights associated with each master node A slave node may be constrained by 1 to 4 other nodes

( 6, 8 ) Data Set - Volumetric heat sources Input: LA, LB, U1, IEL, TIME, TEMP, VALUE Format: 2I2, 1X, I1, 4X, 3I5, E15.0 Content: LA =6 LB =8 U1 = Units for volumetric heat source = 1 for W / m**3 = 2 for cal / cc / sec = 3 for Btu / ft**3 / sec = 4 for Btu / in**3 / sec = 5 for cal / cc / min = 6 for Btu / ft**3 / min = 7 for Btu / in**3 / min IEL = Element number TIME = Time function number TEMP = Temperature function number VALUE = Value of volumetric heat source ( 6, 9 ) Data Set - Linked Periodic Node List Input: LA, LB, M1, N1, I1, M2, N2, I2, M3, N3, I3, M4, N4, I4 Format: 2I2, 1X, 8I7 Contents: LA =6 LB =9 M1-M4 = Node in the first periodic region N1-N4 = Node in the second periodic region, associated with M1-M4 I1-I4 = Periodic index pointing to Data Sets ( 4 6 ) and/or ( 4 7 ) ( 6, 10 ) Data Set - Symmetry boundary condition Input: Format: PAGE D - 22

LA, LB, IEL, FACE 2I2, 1X, 2I5



Content:

LA LB IEL FACE

=6 = 10 = Element number = Element face number ( see Note A )

( 6, 11 ) Data Set - Vent boundary condition Input: Format: Content:

LA, LB, U1, U2, U3, U4, NODE, ITIME, P_EXIT, DIAM, ROUGH, LENGTH 2I2, 1X, 4I1, 1X, 2I7, 4E15.0 LA =6 LB = 11 U1 = Units for pressure = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 U2,U3,U4 = Units of length for DIAM, ROUGH, and LENGTH = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches NODE = Casting side node number where vent is attached ITIME = Time function index for P_EXIT P_EXIT = Pressure at exit of vent DIAM = Vent diameter ROUGH = Vent surface roughness LENGTH = Vent equivalent length

( 6, 12 ) Data Set - Gas Injection Boundary Condition Input: LA, LB, U1, NODE, TIME, PRES, MDOT Format: 2I2, 1X, I1, 4X, 3I5, E15.0 Content: LA =6 LB = 12 U1 = Units for mass flux = 1 kg / sec = 2 g / sec = 3 lb / sec = 4 kg / min = 5 g / min = 6 lb / min NODE = Node that marks the location of the injection site TIME = Time function number modifying MDOT PRES = Pressure function number modifying MDOT MDOT = Gas injection mass flow rate



( 6, 13 ) Data Set - Virtual Mold Data Input: Format: Content:

LA, LB, U1, ELEM, FACE, MAT, GEOM, IHTC, PT 2I2, 1X, I1, 2X, 5I5, E15.0 LA =6 L1 = 13 U1 = Units of length for penetration thickness = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches ELEM = Element number FACE = Face number MAT = Material id number, pointing to Data Set ( 3 1 ) GEOM = Geometry type = 1 for slab = 2 for cylinder = 3 for spherical IHTC = Interface heat transfer pointing to Data Set ( 6 3 ) PT = Penetration thickness of mold

( 6, 15 ) Data Set - Surface load faces Input: Format: Content:

LA, LB, ELEM, FACE, INDEX 2I2, 1X, 2X, 3I5 LA =6 L1 = 15 ELEM = Element number FACE = Face number INDEX = Pointer to Data Set ( 6 16 )

( 6, 16 ) Data Set - Surface load data Input: Format: Content:

PAGE D - 24

LA, LB, U1, INDEX, ITIME, XLOAD, YLOAD ZLOAD 2I2, 1X, I1, 2X, 2I5, 3E15.0 LA =6 L1 = 16 U1 = Units for surface load = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 INDEX = Data set index ITIME = Time function index for surface load XLOAD, = Components of the surface load YLOAD, ZLOAD



( 6, 17 ) Data Set - Point load Input: Format: Content:

LA, LB, U1, NODE, ITIME, XLOAD, YLOAD, ZLOAD 2I2, 1X, I1, 2X, 2I5, 3E15.0 LA =6 L1 = 17 U1 = Units for point load = 1 for dynes = 2 for Newtons = 3 for lbs ITIME = Time function index for point load XLOAD, = Components of the point load YLOAD, ZLOAD

( 6, 18 ) Data Set - Non-aligning interface Input: Format: Content:

LA, LB, U1, INDEX, MID1, MID2, IHTC, TOL1, TOL2 2I2, 1X, I1, 2X, 4I5, 2E15.0 LA =6 L1 = 18 U1 = Units for TOL1 and TOL2 = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches INDEX = Non-aligning interface index MID1 = Material id 1 MID2 = Material id 2 IHTC = Pointer to Data Set ( 6 3 ) TOL1 = In-plane tolerance TOL2 = Perimeter tolerance

( 6, 19 ) Data Set - Fluid momentum sources Input: Format: Content:

LA, LB, U1, ELEM, ITIME, XMOM, YMOM, ZMOM 2I2, 1X, I1, 2X, 2I5, 3E15.0 LA =6 L1 = 19 U1 = Units for momentum source = 1 for Newton / cubic meter = 2 for dyne / cubic centimeter = 3 for lb / cubic feet = 4 for lb / cubic inch ELEM = Element number ITIME = Time function for the momentum source XMOM, = Components of the momentum source YMOM, ZMOM



( 6, 20 ) Data Set - Free surface heat flux Input: Format: Content:

LA, LB, MID, INDEX 2I2, 5X, 2I5 LA =6 L1 = 20 MID = Material id number INDEX = Pointer to Data Set ( 6 1 )

( 6, 21 ) Data Set - Fluid mass source Input: Format: Content:

PAGE D - 26

LA, LB, U1, U2, U3, INDEX, TIMT, TIMS, TIMX, TIMY, TIMZ, TEMP, MDOT, X, Y, Z 2I2, 1X, 3I1, 2X, 6I5, 5E12.0 LA =6 L1 = 21 U1 = Units for source temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine U2 = Units for source mass flow rate = 1 for Kg / sec = 2 for g / sec = 3 for lb / sec = 4 for Kg / min = 5 for g / min = 6 for lb / min U3 = Units of the coordinates X, Y, Z = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches INDEX = Fluid source index TIMT = Time function for the source temperature TIMS = Time function for the source mass flow rate TIMX, = Time function for the source position TIMY, TIMZ TEMP = Temperature of the source MDOT = Mass flow rate of the source X, = Source position Y, Z



( 6, 22 ) Data Set - Current Density Input: Format: Content:

LA, LB, U1, MID, ITIME, CURRENT 2I2, 1X, I1, 2X, 2I5, E12.0 LA =6 L1 = 22 U1 = Units for current density = 1 for amps / ( meters **2 ) = 2 for amps / ( centimeters ** 2 ) = 3 for amps / ( millimeters ** 2 ) = 4 for amps / ( feet ** 2 ) = 5 for amps / ( inches ** 2 ) MID = Material id number ITIME = Time function for current density CURRENT = current density

( 7, 0 ) Data Set - Dirichlet B.C. - Fixed Temperature Input: Format: Content:

LA, LB, U1, NODE, TIME, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =0 U1 = Units for fixed temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine NODE = Node number TIME = Time function number FIXVAL = Value of fixed temperature

( 7, 1 ) Data Set - Dirichlet B.C. - Fixed U Velocity Input:

LA, LB, U1, NODE, INDEX, FIXVAL

Format: Content:

2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =1 U1 = Units for fixed velocity = 1 for m / sec = 2 for cm / sec = 3 for mm / sec = 4 for ft / sec = 5 for in / sec = 6 for m / min = 7 for cm / min = 8 for ft / min = 9 for in / min NODE = Node number INDEX = Pointer to Data Set ( 7, 7 ) FIXVAL = Value of fixed velocity



( 7, 2 ) Data Set - Dirichlet B.C. - Fixed V Velocity Input: Format: Content:

LA, LB, U1, NODE, INDEX, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =2 U1 = Units for fixed velocity = 1 for m / sec = 2 for cm / sec = 3 for mm / sec = 4 for ft / sec = 5 for in / sec = 6 for m / min = 7 for cm / min = 8 for ft / min = 9 for in / min NODE = Node number INDEX = Pointer to Data Set ( 7, 7 ) FIXVAL = Value of fixed velocity

( 7, 3 ) Data Set - Dirichlet B.C. - Fixed W Velocity Input: Format: Content:

PAGE D - 28

LA, LB, U1, NODE, INDEX, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =3 U1 = Units for fixed velocity = 1 for m / sec = 2 for cm / sec = 3 for mm / sec = 4 for ft / sec = 5 for in / sec = 6 for m / min = 7 for cm / min = 8 for ft / min = 9 for in / min NODE = Node number INDEX = Pointer to Data Set ( 7, 7 ) FIXVAL = Value of fixed velocity



( 7, 4 ) Data Set - Dirichlet B.C. - Fixed Pressure Input: Format: Content:

LA, LB, U1, NODE, TIME, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =4 U1 = Units for fixed pressure = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 NODE = Node number TIME = Time function number FIXVAL = Value of fixed pressure

( 7, 5 ) Data Set - Dirichlet B.C. - Fixed turbulence intensity Input: Format: Content:

Note:

LA, LB, NODE, ITIME, INTENS 2I2, 5X, 2I5, E15.0 LA =7 LB =5 NODE = Node number ITIME = Time function number for turbulence intensity INTENS = Value of turbulence intensity as a fraction The turbulence kinetic energy at a prescribed node is calculated as k = 0.5 * ( INTENS **2 ) * ( u**2 + v**2 + w**2 ).

( 7, 6 ) Data Set - Dirichlet B.C. - Fixed turbulence length scale Input: Format: Content:

Note:

LA, LB, U1, NODE, ITIME, LENGTH 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =6 U1 = Units for turbulence length scale = 1 for meters = 2 for centimeters = 3 for millimeters = 4 for feet = 5 for inches NODE = Node number ITIME = Time function number for turbulence length scale LENGTH = Value of turbulence length scale The corresponding turbulence dissipation rate is calculated as e = CMU * k**1.5 / LENGTH. U1 CMU = .09 by default, but can be modified in the prefixp.dat file.



( 7, 7 ) Data Set - Dirichlet B.C. - Additional Information Input: Format: Content:

LA, LB, INDEX, TIME, PRES, FILLIM 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB =7 INDEX = Corresponds to INDEX in Data Sets ( 7, 1 ), ( 7, 2 ), and ( 7, 3 ) TIME = Time function number PRES = Pressure function number FILLIM = Percentage of volume filled before stopping inlet flow

( 7, 8 ) Data Set - Rotating nodes Input: Format: Content:

Note:

LA, LB, NODE 2I2, 5X, I7 LA =7 LB =8 NODE = Node number Nodes in this list will be given the angular velocity as specified in the 4 8 cards. If no 7 8 cards are used, then the no-slip nodes will be given the angular velocity

( 7, 10 ) Data Set - Dirichlet B.C. - Fixed X displacement Input: Format: Content:

LA, LB, U1, NODE, TIME, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB = 10 U1 = Units for fixed displacement = 1 for meter = 2 for centimeter = 3 for millimeter = 4 for feet = 5 for inch NODE = Node number TIME = Time function number FIXVAL = Value of fixed X displacement

( 7, 11 ) Data Set - Dirichlet B.C. - Fixed Y displacement Input: Format: Content:

PAGE D - 30

LA, LB, U1, NODE, TIME, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB = 11 U1 = Units for fixed displacement = 1 for meter = 2 for centimeter = 3 for millimeter = 4 for feet = 5 for inch NODE = Node number TIME = Time function number FIXVAL = Value of fixed Y displacement



( 7, 12 ) Data Set - Dirichlet B.C. - Fixed Z displacement Input: Format: Content:

LA, LB, U1, NODE, TIME, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB = 12 U1 = Units for fixed displacement = 1 for meter = 2 for centimeter = 3 for millimeter = 4 for feet = 5 for inch NODE = Node number TIME = Time function number FIXVAL = Value of fixed Z displacement

( 7, 13 ) Data Set - Dirichlet B.C. - Fixed magnetic potential Input: Format: Content:

Note:

LA, LB, U1, NODE, TIME, FIXVAL 2I2, 1X, I1, 4X, 2I5, E15.0 LA =7 LB = 13 U1 = Units for fixed magnetic potential = 1 for Weber / meter = 2 for Weber / centimeter = 3 for Weber / millimeter = 4 for Weber / feet = 5 for Weber / inch NODE = Node number TIME = Time function number FIXVAL = Value of fixed magnetic potential The magnetic potential is usually set to zero in the far field.

( 8, 0 ) Data Set - Non-uniform I.C. - Temperature Input: Format: Content:

LA, LB, U1, NODE, TIC 2I2, 1X, I1, 4X, I5, E15.0 LA =8 LB =0 U1 = Units for non-uniform initial temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine NODE = Node number TIC = Initial temperature for NODE



( 8, 1 ) Data Set - Non-uniform I.C. - U Velocity Input: Format: Content:

LA, LB, U1, NODE, VIC 2I2, 1X, I1, 4X, I5, E15.0 LA =8 LB =1 U1 = Units for non-uniform initial velocity = 1 for m / sec = 2 for cm / sec = 3 for mm / sec = 4 for ft / sec = 5 for in / sec = 6 for m / min = 7 for cm / min = 8 for ft / min NODE = Node number VIC = Initial u velocity for NODE

( 8, 2 ) Data Set - Non-uniform I.C. - V Velocity Input: Format: Content:

LA, LB, U1, NODE, VIC 2I2, 1X, I1, 4X, I5, E15.0 LA =8 LB =2 U1 = Units for non-uniform initial velocity = 1 for m / sec = 2 for cm / sec = 3 for mm / sec = 4 for ft / sec = 5 for in / sec = 6 for m / min = 7 for cm / min = 8 for ft / min NODE = Node number VIC = Initial v velocity for NODE

( 8, 3 ) Data Set - Non-uniform I.C. - W Velocity Input: Format: Content:

PAGE D - 32

LA, LB, U1, NODE, VIC 2I2, 1X, I1, 4X, I5, E15.0 LA =8 LB =3 U1 = Units for non-uniform initial velocity = 1 for m / sec = 2 for cm / sec = 3 for mm / sec = 4 for ft / sec = 5 for in / sec = 6 for m / min = 7 for cm / min = 8 for ft / min NODE = Node number VIC = Initial w velocity for NODE



( 8, 4 ) Data Set - Non-uniform I.C. - Pressure Input: Format: Content:

LA, LB, U1, NODE, PIC 2I2, 1X, I1, 4X, I5, E15.0 LA =8 LB =4 U1 = Units for non-uniform initial pressure = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 NODE = Node number PIC = Initial pressure for NODE

( 9, X ) Data Set - Linear Temperature Function Input: Format: Content:

LA, LB, U1, CURVE, POINT, TEMP, VALUE 2I2, 1X, I1, 4X, 2I5, 2E15.0 LA =9 LB = 0 for conductivity LB = 1 for film coefficient LB = 2 for interface heat transfer LB = 3 for face emissivity LB = 4 for enclosure emissivity LB = 5 for volumetric heat source LB = 6 for density LB = 7 for specific heat LB = 8 for viscosity LB = 9 for fraction solid LB = 10 for surface tension LB = 11 for partition coefficient LB = 12 for diffusivity LB = 13 for substrate density LB = 14 for phase shift coefficient LB = 15 for power law coefficient LB = 16 for Yasuda coefficient LB = 17 for filter interface heat transfer coefficient LB = 18 for elastic modulus LB = 19 for Poisson ratio LB = 20 for thermal expansion LB = 21 for yield stress LB = 22 for strength parameter LB = 23 for hardening parameter LB = 24 for hardening exponent LB = 25 for visco-plasticity power coefficient LB = 26 for fluidity parameter LB = 27 for magnetic permeability LB = 28 for electrical conductivity U1 = Units for temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine CURVE = Function number APPENDICES, PAGE D - 33


POINT TEMP VALUE

= Number of point on the curve = Temperature of the point = Function value of the point

( 10, X ) Data Set - Time Function Input: Format: Content:

PAGE D - 34

LA, LB, U1, CURVE, POINT, TIME, VALUE 2I2, 1X, I1, 4X, 2I5, 2E15.0 LA = 10 LB = 0 for specified heat flux LB = 1 for film coefficient LB = 2 for ambient temperature LB = 3 for fixed temperature LB = 4 for interface heat transfer LB = 5 for enclosure face velocity LB = 6 for enclosure face temperature LB = 7 for volumetric heat source LB = 8 for fixed velocity LB = 9 for fixed pressure LB = 10 for face emissivity LB = 11 for maximum time step LB = 12 for gas injection mass flux LB = 13 for gravity vector rotation angle LB = 14 for turbulence intensity LB = 15 for turbulence characteristic length LB = 16 for gas vent pressure LB = 17 for angular velocity LB = 18 for displacement LB = 19 for filter interface heat transfer coefficient LB = 20 for surface load LB = 21 for point load LB = 22 for momentum source LB = 23 for mass source flow rate LB = 24 for mass source temperature LB = 25 for mass source x position LB = 26 for mass source y position LB = 27 for mass source z position LB = 28 for moving solid velocity LB = 29 for current density LB = 30 for magnetic potential U1 = Units for time = 1 for sec = 2 for min CURVE = Function number POINT = Number of point on the curve TIME = Time of the point VALUE = Function value of the point



( 11, X ) Data Set - Quadratic Temperature Function Input: Format: Content:

LA, LB, U1, CURVE, POINT, TEMP, A, B, C 2I2, 1X, I1, 4X, 2I5, 2E15.0 LA = 11 LB = 0 for conductivity LB = 1 for film coefficient LB = 2 for interface heat transfer LB = 3 for face emissivity LB = 4 for enclosure emissivity LB = 5 for volumetric heat source LB = 6 for density LB = 7 for specific heat LB = 8 for viscosity LB = 9 for fraction solid LB = 10 for surface tension LB = 11 for partition coefficient LB = 12 for diffusivity LB = 13 for substrate density LB = 14 for phase shift coefficient LB = 15 for power law coefficient LB = 16 for Yasuda coefficient LB = 17 for filter interface heat transfer coefficient LB = 18 for elastic modulus LB = 19 for Poisson ratio LB = 20 for thermal expansion LB = 21 for yield stress LB = 22 for strength parameter LB = 23 for hardening parameter LB = 24 for hardening exponent LB = 25 for visco-plasticity power coefficient LB = 26 for fluidity parameter LB = 27 for magnetic permeability LB = 28 for electrical conductivity U1 = Units for temperature = 1 for Kelvin = 2 for Celsius = 3 for Fahrenheit = 4 for Rankine CURVE = Function number POINT = Number of point on the curve TEMP = Temperature of the point A = Constant coefficient B = Coefficient of temperature C = Coefficient of temperature squared



( 12, X ) Data Set - Pressure Function Input: Format: Content:

LA, LB, U1, CURVE, POINT, PRES, VALUE 2I2, 1X, I1, 4X, 2I5, 2E15.0 LA = 12 LB = 0 for density LB = 1 for fixed velocity LB = 2 for gas injection mass flux U1 = Units for pressure = 1 for N / m**2 = 2 for Pa = 3 for KPa = 4 for MPa = 5 for bar = 6 for dyne / cm**2 = 7 for atm = 8 for psia = 9 for lb / ft**2 CURVE = Function number POINT = Number of point on the curve PRES = Pressure of the point VALUE = Function value of the point

( 13, X ) Data Set - Cooling Rate Function Input: Format: Content:

PAGE D - 36

LA, LB, U1, CURVE, POINT, CRATE, VALUE 2I2, 1X, I1, 4X, 2I5, 2E15.0 LA = 13 LB = 0 for substrate density LB = 1 for transformation temperature LB = 2 for lamellar spacing U1 = Units for cooling rate = 1 for K / sec = 2 for C / sec = 3 for F / sec = 4 for R / sec = 5 for K / min = 6 for C / min = 7 for F / min = 8 for R / min CURVE = Function number POINT = Number of point on the curve CRATE = Cooling rate of the point VALUE = Function value of the point



( 14, X ) Data Set - Concentration Function Input: Format: Content:

LA, LB, U1, CURVE, POINT, CONC, VALUE 2I2, 1X, I1, 4X, 2I5, 2E15.0 LA = 14 LB = 0 for liquidus slope U1 = Units for concentration = 1 for 1 / m**3 = 2 for 1 / cm**3 = 3 for 1 / mm**3 = 4 for 1 / ft**3 = 5 for 1 / in**3 CURVE = Function number POINT = Number of point on the curve CONC = Cooling rate of the point VALUE = Function value of the point

( 99, 0 ) Data Set - Terminator Input: Format: Content:

LA, LB 2I2 LA LB

= 99 to terminate the data file =0



Note A:

Brick Element Face

PAGE D - 38

Local Nodes

1

1

4

3

2

2

1

2

6

5

3

2

3

7

6

4

3

4

8

7

5

4

1

5

8

6

5

6

7

8



4 Node Tetrahedral Element Face

Local Nodes

1

1

3

2

2

2

4

1

3

2

3

4

4

4

3

1



Wedge Element Face

PAGE D - 40

Local Nodes

1

1

3

2

-

2

4

5

6

-

3

1

2

5

4

4

2

3

6

5

5

3

1

4

6



Quadrilateral Element Face

Local Nodes

1

1

2

2

2

3

3

3

4

4

4

1



Triangle Element Face

PAGE D - 42


Local Nodes

1

1

2

2

2

3

3

3

1


10 Node Tetrahedral Element Face

Local Nodes

1

1

3

2

7

6

5

2

2

4

1

9

8

5

3

2

3

4

6

10

9

4

4

3

1

10

7

8




PAGE D - 44


131255138-Procast-Manual.pdf

Recommend Documents