Introduction to Thermal Analysis Using MSC.thermal

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Introduction to Thermal Analysis Using MSC.Thermal PAT312 EXERCISE WORKBOOK MSC.Patran Version 2001

P3*V2001*Z*Z*Z*SM–PAT312–WBK

June 2001

PROPRIETARY NOTICE The MSC.Software Corporation reserves the right to make changes in specifications and other information contained in this document without prior notice. Although due care has been taken to present accurate information, THE MSC.SOFTWARE CORPORATION DISCLAIMS ALL WARRANTIES WITH RESPECT TO THE CONTENTS OF THIS DOCUMENT (INCLUDING WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE) EITHER EXPRESSED OR IMPLIED. THE MSC.SOFTWARE CORPORATION SHALL NOT BE LIABLE FOR DAMAGES RESULTING FROM ANY ERROR CONTAINED HEREIN, INCLUDING, BUT NOT LIMITED TO, FOR ANY SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF, OR IN CONNECTION WITH, THE USE OF THIS DOCUMENT. MSC.Patran is a registered trademark of The MSC.Software Corporation. MSC and MSC. are registered trademarks and service marks of The MSC.Software Corporation. ABAQUS is a registered trademark of Hibbitt, Karlsson, & Sorensen, Inc. ANSYS is a registered trademark of ANSYS, Inc. CADDS 5 and Computervision are trademarks of Computervision R&D Inc., a subsidiary of Prime Computer, Inc. CATIA is a registered trademark of Dassault Systemes. EUCLID is a registered trademark of Matra Datavision, S.A. IGES is an acronym for the “Initial Graphics Exchange Specification”, published by the U.S. Department of Commerce, National Institute of Standards and Technology. MARC is a registered trademark of MARC Analysis Research Corporation. Motif is a trademark of the Open Software Foundation, Inc. MSC.Nastran is an enhanced proprietary version developed, maintained, supported and marketed by The MSC.Software Corporation. NASTRAN is a registered trademark of the National Aeronautics and Space Administration. Pro/ENGINEER is a trademark of Parametric Technology Corporation. Unigraphics is a registered trademark of EDS Unigraphics Division. UNIX is a trademark of AT&T Bell Laboratories. X Window System is a trademark of the Massachusetts Institute of Technology. Training Documentation: Copyright ÿ 2001 The MSC.Software Corporation. All Rights Reserved. This notice shall be marked on any reproduction of this documentation, in whole or in part. Any reproduction or distribution of this document, in whole or in part, without the prior written consent of The MSC.Software Corporation is prohibited. If you would like to order more copies of this document, please contact MSC.Software Contracts Processing at (800) 400-4672. U.S.A. orders: All orders must be accompanied by a check or purchase order. Your order will be sent prepaid via UPS or fourth class mail and the shipping charges will be added to the invoice. F.O.B. will be the shipping point. Terms are net amount due within 30 days. Outside U.S.A. orders: Please contact your local MSC.Software office for a quotation.

DISCLAIMER The concepts, methods, and examples presented in this text are for educational purposes only and are not intended to be exhaustive or to apply to any particular engineering problem or design. The MSC.Software Corporation assumes no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information contained herein.

Printed in U.S.A. ©2001 by MSC.Software Corporation All rights reserved.

TABLE OF CONTENTS MSC.Patran Introduction to Thermal Analysis Using MSC.Thermal PAT312 Exercise Workbook Release 2001

Workshop

Title

Exercise 1

Construct Hybrid Microcircuit Geometry . . . . . . . . . . .1-1 Geometry Creation

Exercise 2

Hybrid Microcircuit Finite Elements. . . . . . . . . . . . . . . .2-1 Meshing

Exercise 3

Equivalence and Verify the Hybrid Mesh . . . . . . . . . . . .3-1 FEM Verification Tools

Exercise 4

Materials, Lists and Groups. . . . . . . . . . . . . . . . . . . . . . .4-1 Define material properties using lists and groups

Exercise 5

Thermal Analysis using Imported CAD Geometry . . . . .5-1 Create and analyze model with imported geometry

Exercise 6

Comparison of Two Heat Sink Designs . . . . . . . . . . . . .6-1 2D axisymmetric model with simple convection

Exercise 7

An Oven Window Design . . . . . . . . . . . . . . . . . . . . . . . .7-1 2D planar model with field definition for LBC, simple convection

Exercise 8

Temperature Dependent Material Properties. . . . . . . . . .8-1 2D planar model with field definition for material properties

Exercise 9

Thermal Analysis of the Hybrid Microcircuit . . . . . . . . .9-1 Create convection and loading LBCs, submit analysis and view results

Exercise 10

Time Dependent Boundary Conditions . . . . . . . . . . . . . .10-1 Using microfunctions for transient analysis

Exercise 11

Using Convection Correlations . . . . . . . . . . . . . . . . . . . .11-1 Using the convection correlation library Copyright ÿ 2001 MSC.Software

Workshop

Title

Exercise 12

Analysis of a Fuel Nozzle Tip . . . . . . . . . . . . . . . . . . . . .12-1 Advective, radiative and convective boundaries, convective quads

Exercise 13

A Sprinkler System Hydraulic Analysis . . . . . . . . . . . . .13-1 Pressure varying mass flow

Exercise 14

Midterm: Build a Simple 2 Plate Model . . . . . . . . . . . . .14-1 Radiation heat transfer, analysis utilities

Exercise 15

User Supplied Subroutines . . . . . . . . . . . . . . . . . . . . . . .15-1 User subroutine convection calculations

Exercise 16

A Concentric Tube, Counterflow Heat Exchanger . . . . .16-1 Element sweep, gap convection

Exercise 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17-1 Advective, radiative and convective boundaries

Exercise 18

Post-processing the Hybrid Microcircuit Results with Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-1 Insight tools

Exercise 19

Animating Results with Insight . . . . . . . . . . . . . . . . . . . .19-1 Insight and Patran animation

Exercise 20

SINDA Translation of a PWB Model . . . . . . . . . . . . . . .20-1 Read session file, produce SINDA deck

Exercise 21

Optimizing Performance of Radiation Interchange Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . .21-1 Flags and settings to increase run efficiency

Exercise 22

Steady State Radiative Boundary Conditions . . . . . . . . .22-1 2D planar model with radiation within enclosures

Exercise 23

Your Model Here . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23-1 User initiated model

Copyright ÿ 2001 MSC.Software

WORKSHOP 1

Construct Hybrid Microcircuit Geometry 1 8

9

8

9

6

7

6

7

10 1 2 2

3 3

4 4

5 5

Y Z

X

Objective: ■

In this exercise you will construct a trimmed surface which will be the underlying geometry of a 3D Hybrid Microcircuit model.

■

Create a trimmed surface with interior cutouts for components.

■

Create regular surfaces representing component footprints.

MSC.Patran 312 Exercise Workbook - Release 2001

1-1

1-2


WORKSHOP 1

Construct Hybrid Microcircuit Geometry

Model Description: In this exercise you will create the required geometry for a 3D hybrid microcircuit model. You will first construct simple surfaces which will define the microcircuit perimeter and the locations of eight surface mounted devices. From the edges of these simple surfaces you will create chained curves which define the inner and outer edges (loops) of the microcircuit surface. From these chained curves you will create a trimmed surface, the guiding geometry of the microcircuit model. In later exercises you will define the finite element mesh, material properties, thermal loads, and boundary conditions for the microcircuit.

Exercise Overview: ■

Create a new database named microcircuit.db. Set the Tolerance to Based on Model, the Approximate Maximum Model Dimension to 0.02, and the Analysis Code to MSC/THERMAL.

■

Create a simple surface that will form the outside edge for the microcircuit model. The dimensions are provided.

■

Turn labels on using Tool Bar Show Labels icon.

■

Create eight regular surfaces that will define the locations of the surface mounted devices. The dimensions are provided.

■

Create chained curves on the edges of each surface by using Create/Curve/Chain.

■ ■

Unclutter the display by selectively hiding labels. . Complete the geometry of the hybrid microcircuit by using Create/Surface/Trimmed with the Option Planar.

■

Quit MSC.Patran.


1-3

Hybrid Microcircuit Dimensions

Hybrid Microcirc uit

0.004

0.002

0.006 X 0.001 (typical) 0.0026

0.02

0.0094

0.002 X 0.002 (typical)

0.004

0.004

0.004

0.02

Figure 1 -Board Design

(All lengths shown in meters)

Exercise Procedure: Create a new database

1.

Create a new database named microcircuit.db. Set the Tolerance to Based on Model, the Approximate Maximum Model Dimension to 0.02, and the Analysis Code to MSC/THERMAL.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name microcircuit.db to the new database by clicking in the New Database Name box and entering microcircuit (.db will automatically be appended). Select OK to create the new database. 1-4


WORKSHOP 1


MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Based on Model, the Approximate Maximum Model Dimension to 0.02, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. 2.

Create a simple surface that will form the outside edge for the microcircuit model.

Select the Geometry toggle in Applications radio button. You will now create a 0.02 X 0.02 surface. Use its outside edges to form the outer loop for the trimmed surface you will create in the last part of this exercise.

Create a simple surface

Set the Action, Object, and Method to Create/Surface/ XYZ. Be sure to turn off Auto Execute in all forms in this exercise. Change the Vector Coordinates List to <0.02 0.02 0> and select Apply to create the surface. The completed form is shown below. Geometry Action:

Create

Object:

Surface

Method:

XYZ

Surface ID List 1 Surface Type PATRAN 2 Convention

Refer. Coordinate Frame Coord 0 Vector Coordinates List <0.02 0.02 0> Auto Execute Origin Coordinates List [0 0 0]

-ApplyMSC.Patran 312 Exercise Workbook - Release 2001

1-5

Turn on labels

3.

Turn on labels

Turn labels on using Tool Bar Show Labels icon.

Use the Tool Bar Show Labels icon on the menu bar to turn on labels. The correct model is shown below.

2

3

1

Y Z

4.

Position the 8 devices

X 1

4

Create eight regular surfaces that will define the locations of the surface mounted devices.

Position the left-most square device by changing the Vector and Origin Coordinates Lists to <0.002 0.002 0> and [0.004 0.004 0]. Select Apply to create the surface.

1-6


WORKSHOP 1


Create three copies of this region by changing the Action, Object, and Method to Transform/Surface/Translate. Enter <0.004 0 0> for the Translation Vector and 3 for the Repeat Count. Click in the Surface List box. Select Surface 2 in the viewport. Select Apply to create the surface. The completed Geometry form and current model should appear as shown below. Geometry Action:

Transform

Object:

Surface

Method:

Translate

Surface ID List 3 Type of Transformation in Refer. CF ◆ Cartesian Curvilinear in Refer. CF ◆ ◆

2

3

Refer. Coordinate Frame Coord 0 Translation Vector <0.004 0 0>

1

Translation Parameters Repeat Count 3 Delete Original Surfaces Auto Execute Surface List

6 7 10 11 14 15 18 19 3 4 5 2 5 8 9 1213 16 17 20

Y Z

X

1

4

Surface 2 -Apply-

Leaving the Action as Transform change the Object and Method to Point/Translate. Edit the Translation Vector to read <0 0.0094 0> and the Repeat Count to 1. Click in the Point List box and select Point 5 from the viewport, the lower left corner point of Surface 2. Select Apply to create the surface. Point 21 should appear to guide layout of the remaining four devices. MSC.Patran 312 Exercise Workbook - Release 2001

1-7

Position the 8 devices

Set the Action, Object, and Method to Create/Surface/ XYZ. Position the first rectangular device by changing the Vector Coordinates List to <0.006 0.001 0>, clicking in the Origin Coordinates List box, and selecting Point 21 from the viewport. Select Apply to create the surface. After constructing Surface 6 use the Transform/ Surface/Translate operations twice to complete the remaining three device locations. Forms are shown below. Geometry

Geometry Action:

Create

Object:

Surface

Method:

XYZ

Surface ID List 6

Action:

Transform

Action:

Transform

Object:

Surface

Object:

Surface

Method:

Translate

Method: Translate Surface ID List 7

Surface ID List 8

Type of Transformation

Type of Transformation

in Refer. CF ◆ Cartesian Curvilinear in Refer. CF ◆ ◆

in Refer. CF ◆ Cartesian ◆ Curvilinear in Refer. CF ◆

Refer. Coordinate Frame Coord 0



Vector Coordinates List <0.006 0.001 0>

Translation Vector <0.008 0 0>

Translation Vector <0 0.0026 0>

Surface Type PATRAN 2 Convention

Auto Execute Origin Coordinates List Point 21 -Apply-

Translation Parameters Repeat Count 1 Delete Original Surfaces Auto Execute Surface List Surface 6 -Apply-

1-8

Geometry


Translation Parameters Repeat Count 1 Delete Original Surfaces Auto Execute Surface List Surface 6 7 -Apply-


WORKSHOP 1

Your model should now appear as shown below. 2

3

30

31

34

35

8

9

29 22

32 23

33 26

24

25

36 27

6

7

21

28

1

6

7

10

8

9

2 5

11

14

12

13

3

15

18

16

17

4

19 5 20

Y 1

Z

4

X

5.

Create chained curves on the edges of each surface.

In order to facilitate picking, use Preferences/Picking... and set Rectangle/Polygon Picking to Enclose entire entity. Select Close. Next, Change the Action, Object, and Method to Create/Curve/Chain. Turn off the Delete Constituent Curves option. To create the perimeter chain click in the Curve List box and then click in the Edge selection icon (third from the top) in the Select Menu. While holding the key down select the four outer edges of Surface 1. The completed form should now look like the one shown below. Geometry Action:

Create

Object:

Curve

Method:

Create chained curves

Chain

Curve ID List 1 Auto Chain... Delete Constituent Curves Curve List Surface 1.1 1.2 1.3 1.4

-Apply-

Select Apply to complete the function. MSC.Patran 312 Exercise Workbook - Release 2001

1-9

Unclutter the display

To create the 8 interior chained curves click in the Curve List box and drag a rectangle around Surface 2 (the lower left-most device location). The 4 edge identifiers for Surface 2 should replace the previous Curve List box entry. Select Apply to complete the function. Repeat this step for the remaining seven device surfaces. 6.


Unclutter the display by hiding some labels.

To simplify the displayed image of your model select Display from the Menu Bar and select Entity Color/ Label/Render... from the drop-down menu. When the Entity Color/Label/Render Display form appears select Hide All Entity Labels and turn on only Curve, Surface, and TSurf labels. Select Apply then Cancel to complete the function. Your model should now appear as shown below.

1 8

9

8

9 6

7

6

7

1 2 2

3 3

4 4

5 5

Y Z

X

7.

Create a trimmed surface

Complete the geometry of the hybrid microcircuit.

Create the trimmed surface that surrounds the microcircuits devices. Set Action, Object, and Method to Create/Surface/Trimmed. Select Option as Planar. Turn off the Delete Outer and Inner Loops switches. Click in the Outer Loop List databox, click in the Curve selection icon (second from the top) in the Select Menu and select 1-10


WORKSHOP 1


Curve 1. Next, click in the Inner Loop List databox and drag a rectangle around Curves 2 through 9. The completed Geometry form is shown below for your reference. Geometry Action: Create Object:

Surface

Method:

Trimmed

Surface ID List 10 Surface Type PATRAN 2 Convention Option:

Planar

Auto Chain... Use All Edge Vertices Delete Outer Loop Outer Loop List Curve 1 Delete Inner Loops Inner Loop List Curve 2:9

-Apply-

Select Apply to complete the function. Your model should now appear as shown on the front panel of this exercise. If it does not, select Viewing from the Menu Bar and select Fit View from the drop-down menu. 8.

Quit MSC.Patran.

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.


Quit MSC.Patr

1-11

Quit MSC.Patran

1-12


WORKSHOP 2

Hybrid Microcircuit Finite Elements

Objective: ■

■

In this exercise you will mesh the 3D Hybrid Microcircuit model in two steps. You will use both the IsoMesh and Paver mesher options to create a surface mesh. These surface elements will then be swept into solid elements.


2-1

2-2


WORKSHOP 2


Model Description: In this exercise you will create a mesh for the 3D hybrid microcircuit model. You will use a finite element construction method called 2 1/2 D-meshing to create your 3D finite element model. This algorithm is an extension to the IsoMesh or Paver algorithms because it will create elements where no geometry exists. The mesh will be created in a two step process. First the surface geometry will be meshed using both the IsoMesh and Paver options. The resulting surface elements will be used as a template to create a solid mesh of hexahedral elements. Finally the quadrilateral surface elements are deleted.


Open the existing database named microcircuit.db.

■

Using Show/Surface/Normal verify that all surface normals point in the +Z direction. If necessary, edit normals using Edit/Surface/Reverse.

■

Delete Surface 1 by using Delete/Any and selecting Surface 1.

■

Mesh the regions containing the devices using Create/Mesh/Surface and the IsoMesh Mesher.

■

Sweep/Element/Normal to create device hex elements.

■

Switch to the Paver Mesher and mesh the remaining trimmed surface geometry.

■

Sweep/Element/Normal with One Way Bias in the .- Z direction from all surface quads to create substrate hex elements.

■

Use Finite Elements/Delete/Any and the Select Menu filter to delete all surface quad elements.

■

Unclutter the display by hiding labels.

■

Quit MSC.Patran.


2-3

Open an existing database

Exercise Procedure: Open an existing database

1.


Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select Open… from the drop-down menu. Select the name microcircuit.db from the Database List box.Select OK to open the database. MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. From the Menu Bar select Viewing/Named View Options... Select isometric_view then Close. Select Viewing/Fit View to readjust the display, if necessary. This will provide a convenient view for verifying normal vectors.

Verify surface normals

2.

Verify that surface normals point in the +Z direction.

Select the Geometry Applications radio button. Set the Action, Object, and Method to Show/Surface/Normal. Select Set Normal Vector Length and enter a Normal Vector Length of 0.01. Click in the Surface List box and drag a rectangle around all the displayed geometry. Select Apply. All normal vectors should point in the global +Z direction.

2-4



WORKSHOP 2

If some surfaces have incorrect normal vectors use Edit/ Surface/Reverse in the Geometry form, as shown below, to point the normals in the +Z direction. Geometry Action:

Edit

Object:

Surface

Method:

Reverse

Reverse Associated Elements Auto Execute Surface List

Draw Normal Vectors Reset Graphics -Apply-

3.

Delete Surface 1.

Set the Action and Object to Delete/Any. Click in the Geometric Entity List box and select Surface 1 from the viewport. Use the shift-right mouse button to cycle pick between Surface 10 and Surface 1 or select Surface 1 from the Selection list window, if necessary. Select Apply to delete Surface 1. Repaint the screen with the Refresh Graphics paint brush icon.


Delete Surface 1

2-5

IsoMesh device regions

4.

IsoMesh device regions

Mesh the device regions with an IsoMesh.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Set the Global Edge Length to 0.0012. Click in the Surface List box and while holding down the key select the eight interior device surfaces with the left mouse button. The completed form is shown below.

Finite Elements Action:

Create

Object:

Mesh

Type:

Surface

Output IDs Node ID List 1 Element ID List 1 Global Edge Length 0.0012 Element Topology Quad4 Quad5 Quad8

8

6

6

1 9

9

7

7

10 2

2

Mesher

Y

◆Paver ◆IsoMesh◆

8

Z

3

3

4

4

5

5

X

IsoMesh Parameters... Node Coordinate Frames...

Surface List Surface 2:9 -Apply-

Select Apply to complete the meshing function. The display should appear as shown above. If it does not, select the undo icon and analyze the error to a resolution. 2-6



WORKSHOP 2

5.

Create device hex elements.

Set the Action, Object, and Method to Sweep/Element/ Normal. (If the Mesh Control form appears click OK to accept the defaults.) Change the Normal Length to 0.001. Click in the Base Entity List box and drag a rectangle around the eight sets of quad elements. Select Apply to complete the meshing function. The completed form and resultant display are shown below.

Create device hex elements

Finite Elements Action: Object: Method:

Sweep Element Normal

Output IDs Element ID List 37 Node ID List 85

1

8 6

FE Parameters... Mesh Control... Normal Length 0.001

9 7

10 2

Offset 0.0

Y

Reverse Normal Direction Delete Original Elements

Z

3

4

5

X

Base Entity List Elm 1:36

-Apply-

6.

Mesh the remaining trimmed surface with Paver.

Set the Action, Object, and Method to Create/Mesh/ Surface. The Global Edge Length should be set to 0.0012. Select Paver as the Mesher option. Click in the Surface List box and select the remaining unmeshed trimmed surface, Surface 10. Select Apply to complete the function. If you experience any problems selecting Surface 10, use Preferences/Picking.../(Single Picking) Centroid. MSC.Patran 312 Exercise Workbook - Release 2001

Create the substrate Paver

2-7

Create the substrate hex mesh

7.

Create the substrate hex mesh

Sweep a one-way-biased mesh of hex elements in the - Z direction from all surface quads.

Set the Action, Object, and Method to Sweep/Element/ Normal. (If the Mesh Control form does not appear click on Mesh Control...) In the Mesh Control form change the Method to One Way Bias set Number to 3 and L2/L1 to 4. Select OK to close the Mesh Control form. In the Finite Elements form set Normal Length to 0.005 and turn on Reverse Normal Directions. Click in the Base Entity List box and drag a rectangle around all of the elements in the viewport. (The default Select Menu filter will allow selection of only the quad/tri elements.) The form should appear as shown below. Mesh Control

Finite Elements Action: Object: Method:

Sweep Element Normal

Method: One Way Bias

Mesh Control Data L1

Output IDs Element ID List 400 Node ID List 611

L2

◆ Num Elems and L2/L1 ◆ L1 and L2 ◆ Number = 3 L2/L1 =

4

FE Parameters...

OK

Mesh Control... Normal Length 0.005 Offset 0.0

1

8 6

Reverse Normal Direction

9 7

Delete Original Elements

10

Base Entity List Elm 1:36 109:424

2

3

4

5

Y

-Apply-

Z

X

Select Apply to complete the meshing function. The resultant display is shown above. 2-8



WORKSHOP 2

8.

Delete all surface quad elements.

In the Finite Elements form set Action and Object to Delete/Any.

Delete all quad elements

Click in the Finite Element Entity List box. In the Select Menu choose the quad element filter icon (third from the top), in the second level Select Menu choose the quad element filter (fifth from the top), and drag a rectangle around all entities displayed in the viewport. The form should now appear as shown below.

Finite Elements Action: Object:

Delete Any

Delete Node and Related Empty Groups Element and Related Node Empty Groups MPC's Node Empty Groups Auto Execute Finite Element Entity List Elm 1:36 109:424

-Apply-

Select Apply to complete the function.


2-9



9.

Unclutter the display by hiding labels.

To simplify the display of your model select Display from the Menu Bar and select Plot/Erase... from the drop-down menu. When the Plot/Erase form appears select Posted Entities/Geometry:Erase. Select OK to close the form. Select Display from the Menu Bar and select Entity Color/Label/Render… from the drop-down menu. When the Entity Color/Label/Render form appears select Hide All Entity Labels. Click in the Render Style: box and select Hidden Line or use Hide Labels and Hidden Line icons shown to the right. Select Apply then Cancel to complete the function.

Your model should now appear as shown on the front panel of this exercise. Reset the Render Style to Wireframe.

Quit MSC.Patr

2-10

10.

Quit MSC.Patran.

Select File on the Menu Bar and select Quit from the dropdown menu.


WORKSHOP 3

Equivalence and Verify the Hybrid Mesh

Y Z

X

Objective: ■

■

In this exercise you will equivalence the 3D Hybrid Microcircuit model mesh. You will sample the finite element verification functions to examine the aspect ratio, skewness, and taper of the mesh elements.


3-1

3-2


WORKSHOP 3


Model Description: The hybrid microcircuit is monolithic: all material interfaces have negligible resistance to heat transfer. Hence, there are no contact resistances modeled in the structure and the entire model is materially continuous. In this exercise you will identify any incongruities, “cracks”, in the finite element mesh and equivalence to eliminate them. You will examine the completed mesh with quantitative verification tools. You will evaluate the mesh element aspect ratio, taper, and skewness. These are generally useful in qualitatively assessing the accuracy of results and identifying problem areas for convergence to a solution.



■

Use Finite Element/Verify/Element/Boundaries to identify any “cracks” which remain as artifacts from the geometry creation and meshing process.

■

Equivalence/All/Tolerance Cube to eliminate duplicate nodes and eliminate “cracks” in the mesh.

■

Verify/Hex/Aspect to identify elements with aspect ratios greater than 3.0.

■

Verify/Hex/Face Skew to identify elements with face skew angles greater than 110 degrees.

■

Verify/Hex/Face Taper to identify elements with highly tapered faces.

■

Quit MSC.Patran.


3-3


Exercise Procedure: Open an existing database

1.

Open the existing database

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select Open... from the drop-down menu. Select the name microcircuit.db from the Database List box. Select OK to open the database. MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. 2.

Identify cracks in mesh

Identify any “cracks” which remain as artifacts from the geometry creation and meshing process.

To identify mesh boundaries select the Finite Elements Applications radio button. Set the Action, Object, and Test to Verify/Element/Boundaries. Select Apply. The display should appear as shown below.

Y Z

Equivalen ce mesh nodes

3-4

3.

X

Equivalence nodes to eliminate duplicate nodes and eliminate “cracks” in the mesh.

Set the Action, Object, and Method to Equivalence/All/ Tolerance Cube. Select Apply to complete the function. MSC.Patran 312 Exercise Workbook - Release 2001


WORKSHOP 3

The nodes bounding the interior cracks will be circled in the display and the Command Line will indicate that a number of nodes are deleted. Reexamine the mesh boundaries after equivalencing with Verify/Element/Boundaries. Your model should appear as shown on the front panel of this exercise. 4.

Identify elements with aspect ratios greater than 3.0.

In the Finite Elements form set the Action, Object, and Test to Verify/Hex/Aspect. Change the Aspect Ratio to approximately 3.0. Select Apply. Since the paver mesher was used your results may vary from those shown below. Now select Plot Failed Elements Only. The completed form and resultant display are shown below.

Evaluate element aspect

Finite Elements Verify

Action:

Hex

Object:

Aspect

Type:

Reliability Threshold h1 h2

h2 h1

Normalize Analysis Code: MSC/THERMAL 0.

20.

3.07

Aspect Ratio Element Plot Options Color Code Elements Plot Failed Elements Only

Fringe Attributes... Reset Graphics

Apply

Reset


3-5

Evaluate element face skewness

MSC.Thermal is reliable in converging to a solution even with elements of relatively high aspect ratio. However it is left to the analyst to decide whether too large a gradient is resolved across the long dimension of a high aspect ratio element. If this is so then resolving the mesh to a lower aspect ratio in that area will yield more accuracy.

Evaluate element face

5.

Identify elements with face skew angles greater than 110 degrees.

In the Finite Elements form set the Action, Object, and Test to Verify/Hex/Face Skew. Change the Face Skew Angle to approximately 20.0. Select Apply. Since the paver mesher was used your results may vary from those shown below. Now select Plot Failed Elements Only. The completed form and resultant display are shown below. Finite Elements Verify

Action:

Hex

Object: Type:

Face Skew

Reliability Threshold α

×°-α) (90


90.

20.05

Face Skew Angle Element Plot Options Color Code Elements Plot Failed Elements Only Fringe Attributes... Reset Graphics Apply

3-6

Reset



WORKSHOP 3

The finite element formulation of an R-C network in MSC.Thermal has been developed to provide a higher order accuracy to the resultant temperature distribution than is available with the traditional lumped mass/element centroid technique. Hence, even meshes with skewed elements yield results which do not contain artifacts of the mesh geometry. 6.

Identify elements with highly tapered faces.

In the Finite Elements form set the Action, Object, and Test to Verify/Hex/Face Taper. Change the Face Taper to approximately 0.90. Select Apply. Since the paver mesher was used your results may vary from those shown below. Now select Plot Failed Elements Only. The completed form and resultant display are shown below.

Evaluate element face taper

Finite Elements Verify

Action:

Hex

Object: Typet:

Face Taper

Reliability Threshold

4a A

a


.90

1.

Face Taper Element Plot Options Color Code Elements Plot Failed Elements Only Fringe Attributes... Reset Graphics Apply

Reset


3-7

Quit MSC.Patran

The verification functions in MSC.Patran provide a tool for quantifying the geometric quality of a finite element mesh. The criteria which determine the performance of the mesh in a numerical analysis remain the province of the analyst and his or her experience with the particular analysis. Click Reset Graphics in the Finite Elements Verify form.

Quit MSC.Patr

3-8

7.

Quit MSC.Patran.



WORKSHOP 4

Materials, Lists, and Groups

Objective: ■

■

In this exercise you will define material properties and apply them as element properties on the hybrid microcircuit mesh. You will also use lists and groups as tools to more easily manipulate your model.


4-1

4-2


WORKSHOP 4


Model Description: In this exercise you will define several groups which will contain subsets of model entities. These groups can facilitate model manipulation. You will define materials by entering the data manually based on the information provided These materials will be applied as element properties. Lists will be used to demonstrate their utility in completing the application and verification of element properties. As you progress, carefully review your steps to ensure that you have repeated each step, if necessary, for each material, group, and property definition.



■

Use Create//Isotropic/Manual Input to define the five materials used in this model.

■

Use Group/Create to define a group containing only geometry, another containing only FEM entities, and two more groups dividing the substrate FEM and the device FEM.

■

Use Properties/Create/3D/Thermal 3D Solid to apply the material properties to 4 of the 5 material regions; intentionally ignore the silicon region.

■

Use List/Create... and List/Boolean...to identify elements which have not had a material property . applied.

■

Complete application of material properties using the ‘listc‘ contents as input.

■

Quit MSC.Patran.


4-3

Hybrid Microcircuit Materials

Hybrid Microcirc uit Figure 1-Material Location

A B C

D

E

A B

Substrate Layers Devices & Solder

Table 1-Material Information Material

(A) (B) (C) (D) (E)

4-4

Silicon Solder Alumina Molybdenum Kovar


Conductivity (w/m-C) 148.0 35.7 30.1 139.0 13.9


WORKSHOP 4

Exercise Procedure: 1.

Open the existing database

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window.


Next, select File from the Menu Bar and select Open… from the drop-down menu. Select the name microcircuit.db from the Database List box. Select OK to open the database. MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. 2.

Define the five materials used in this model.

Define a material by selecting the Materials Applications radio button. Set the Action, Object, and Method to Create/Isotropic/Manual Input. Enter the Material Name Silicon and select Input Properties... to enter the data. In the Input Options form enter the value provided in Table 1 for Thermal Conductivity. Enter 1.0 for Density and Specific Heat; these are inert values which are required in the form but not used in a steady-state analysis. The completed form should look as follow.


Define materials

4-5

Define materials

Input Options Constitutive Model:

Materials Action:

Thermal Properties

Property Name

Object:

Value

Thermal Conductivity =

148.0

Density =

1.0

Specific Heat =

1.0

Method:

Create Isotropic Manual Input

*

Filter

Existing Materials

[Phase change temperature] [Latent Heat] =

Time, Temperature or Constant Fields: Material Name Silicon Description Date: 15-Nov-95 Time: 09:48:33

Current Constitutive Models:

Code: MSC/THERMAL -Apply-

Clear

Cancel

Type: Thermal Input Properties... Change Material Status...

Select Apply to define the material. Without closing the Input Options form edit the Material Name and repeat the steps for the remaining four materials renaming them appropriately, Solder, Alumina, Molybdenum, and Kovar. Each time enter the correct thermal conductivity without changing the density or the specific heat. Hit Apply with completion of each material. Select Cancel to close Input Options. After completing the material definitions deselect the Material Application radio button.

4-6


WORKSHOP 4

3.

Materials, Lists, and Groups Divide the geometry and FEM into working groups.

Select Group from the Menu Bar and select Create… from the drop-down menu. Click in the New Group Name box and enter hybrid_geom; click in the Group Contents: menu and select Add All Geometry. The completed form is shown below.

Define geometry and FEM groups

Group Create Action:

Create

Current Viewport default_viewport

Filter

*

Existing Group Names default_group

New Group Name hybrid_geom Make Current Unpost All Other Groups Group Contents: Add All Geometry -Apply-

Cancel

Select Apply to complete the function. Reselect Group/Create, if necessary. Click in the New Group Name box enter hybrid_fem click in the Group Contents: menu and select Add All FEM. Turn on Unpost All Other Groups. Select Apply to complete the function. From the Menu Bar select Viewing/Named View Options... Select side_view then Close. Select Viewing/ Fit View to readjust the display. This is a convenient view for creating the next two groups.This can also be accomplished using the Tool Bar Right Side View icon.


4-7

Define geometry and FEM groups

Reselect Group/Create, if necessary. Click in the New Group Name box enter substrate_fem. Click in the Group Contents: menu and select Add Entity Selection. Turn off Make Current, Posted, and Unpost All Other Groups. From the Select Menu select the Select any FEM entity filter, third icon from the top; from the next level Select Menu select the Element filter, also third from the top; finally, in the third level Select Menu select the Hex element filter, eighth from top. Drag a rectangle around the perimeter of the substrate selecting only the 3 layers of substrate hex elements. The form is shown below. Group Create Action:

Create

Current Viewport default_viewport Filter

*

Existing Group Names default_group hybrid_geom hybrid_fem

New Group Name substrate_fem Make Current Posted Unpost All Other Groups Group Contents: Add Entity Selection

Entity Selection Elm 425:1480

-Apply-

Cancel

Select Apply to complete the function. Repeat these steps dragging a rectangle around only the device area and solder to create the last group named device_and_solder. After all groups are defined, Cancel the Group Function.

4-8



WORKSHOP 4

4.

Apply the material properties to 4 of the 5 material regions; intentionally ignore the silicon region.

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/3D/Thermal 3D Solid. Enter Property Set Name prop_kovar. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and select Kovar from the Material Properties Sets list. Select OK to close the form.

Apply element properties

Click in the Select Members box. From the at the bottom of the screen select the Select a Solid element filter, second icon from the top, and drag a rectangle around the lowest layer of hex elements, region E in Figure 1. The completed form is shown below. Select Add then Apply to complete the function. Element Properties

Input Properties

Action:

3D SOLID Property Name

Value

Material Name

m:Kovar

Value Type

Create

Dimension: 3D Type:

Thermal 3D Solid

Mat Prop Name

[Material orient.-X]

Real Scalar

[Material orient.-Y]

Real Scalar

[Material orient.-Z]

Real Scalar

Existing Property Sets

Property Set Name

prop_kovar Option(s): FE hex, tet, wedge

Material Property Sets

Input Properties...

Silicon Solder Alumina Molybdenum Kovar

Application Region Select Members

Elm 1129:1480 Add

OK

Remove

Application Region

-Apply-

Repeat these steps for the next three layers of elements naming the properties prop_moly, prop_alumina, and prop_solder. Be certain to select the appropriate material for each layer. Omit assigning element properties to the silicon devices. Refer to Figure 1 for material locations. MSC.Patran 312 Exercise Workbook - Release 2001

4-9

Using lists to find elements

We are intentionally omitting the application of a material property to some elements. However, it is not unusual in practice to inadvertently omit assigning an element property to some elements. Use lists to recover them. 5.

Using lists to find

Identify elements which do not have a material property applied.

Select Tools from the Menu Bar and select List from the drop-down menu and Create… from the submenu. Set the Model, Object, and Method to FEM/Element/ Association. In the Association frame scroll to and select Group. In the Existing Groups frame select hybrid_fem. Select Apply. All elements will be listed in ‘lista‘ contents:. Find Target List at the bottom of the Create List form select “B”. Set the Model, Object, and Method to FEM/Element/ Attribute. In the Attribute list select Material. In the Existing Materials list drag through all listed materials and select all materials. Select Apply. Elements with defined materials are listed in ‘listb‘ contents:. The resulting forms are shown below. Model:

Create List FEM

Element Object: Method: Association Association Surface Face Solid Node Group

List A `lista` contents: Element 37:108 425:1480

Method:

Add To Group... Remove From Group...

Filter Specification *

Highlight

Clear

Previous

Cancel

Element 37:72 425:1480

Remove From Group...

◆ ◆ “B” ◆

Apply

4-10

Cancel

Attribute Select Property Set Material Fringe Value Filter Specification * Existing Materials

List B `listb` contents:

Add To Group... Target List “A”

Attribute

Filter

Filter Existing Materials default_group device_fem hybrid_fem hybrid_geom substrate_fem

Create List FEM Model: Element Object:

Highlight

Clear

Previous

Cancel


Silicon Solder Alumina Kovar

Target List

◆ “A” ◆ ◆ “B” Apply

Cancel


WORKSHOP 4

Since Lista A contains all elements and List B contains all elements with a material attribute, subtracting List B from List A will yield List C which will contain all elements which do not have material attributes. Select Tools/List from the Menu Bar and select Boolean… from the submenu. The Boolean List form will offer several options for Boolean operations, choose the AB icon. The variable ‘listc‘ now contains the desired element list. Select Cancel to exit the Boolean List and select Cancel again to exit the Create List form. The contents of ‘lista‘, ‘listb‘, and ‘listc‘ are retained. MSC.Patran supplies a set of utilities collected under the name Utilities. When installed, Utilities provides a utility, Utilities/Group/Group Elements with No Properties..., which accomplishes the preceding steps in three mouse clicks. We will discuss and use Utilities in later lectures and exercises. 6.

Complete application of material properties using the ‘listc‘ contents as input.

To complete element properties return to Create/3D/ Thermal 3D Solid. Input the Property Set Name prop_silicon. Complete the Input Properties form by selecting Silicon from the Material Property Sets. In the Select Members box type ‘listc‘ (use reverse apostrophes). Notice that ‘listc‘ is evaluated in the Application Region. Select Add then Apply to complete the function.

Complete the element

From the Menu Bar select Viewing/Named View Options... from the drop-down menu. Select isometric_view then Close. Or use Tool Bar Iso 1 View icon.

In the Element Properties form set Action as Show, in Existing Properties select Material Name, and in Display Method select Scalar Plot. Select Groups as hybrid_fem and select Apply. The model should now appear as on the front panel of the exercise. 7.

Quit MSC.Patran

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu. MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr 4-11

Quit MSC.Patran

4-12


WORKSHOP 5

Thermal Analysis using Imported CAD Geometry

Objective: ■

In this exercise you will complete a thermal analysis of a model created from imported CAD geometry.


5-1

5-2


WORKSHOP 5

Thermal Analysis using Imported Geometry

Model Description: In this exercise analyze an oven lid clamp. The clamp geometry (in centimeters) will be imported as ProEngineer geometry; from it, create a Brep solid. Use the Auto TetMesh Mesher to mesh the solid. Apply boundary conditions, complete the analysis and review the results. This stainless steel (MID 364) clamp is used to clamp the perimeter flange on a pressurized processing oven lid. The oven lid surface can reach 300oC for several days. The lid is insulated; the insulation is sometimes pierced by the clamp edge. The clamp mounting boss is fastened with two bolts and thermal grease (total contact h = 0.01 w/oC-cm2) to a room temperature (20oC) water cooled sink. Determine both that the bracket mounting boss will remain at or below 50oC to ensure safe handling during disassembly and that the spring tab knee and boss transition areas remain at or below 150oC to prevent loss of clamping force due to creep. This exercise will introduce a different format for guiding data entry, keystrokes, and mouse operations. Though all actions and entries required to accomplish a given step are provided some additional synthesis may be required by the user since exact images of the entry forms are not provided.


Open a new database named exercise_05.db.

■

Import Pro/ENGINEER primitive geometry from a file named oventab.geo.

■

Create a B-rep solid from these surfaces and delete the original surfaces in the process.

■

Mesh the solid with the TetMesh Mesher using Tet4 elements, a global edge length of 2.5..

■

Define an element property over all the solid elements using a material name of 364.

■

Create a boundary sink node 999 below the mounting boss and not associated with geometry.

■

Change the view for application of boundary conditions

■

Apply a 20oC fixed temperature to the sink node.

■

Apply a fixed temperature of 300oC to the edge of the solid in contact with the lid. MSC.Patran 312 Exercise Workbook - Release 2001

5-3

Open a new database ■

Apply a convection boundary condition of 0.01 w/oCcm2 to the underside of the mounting boss.

■

Select the mpidcgs.bin file in the P/Thermal Translation Parameters form in order to select the correct material property units.

■

Run the analysis and read the results into the database.

■

Fringe plot the temperature results and evaluate them against the requirements.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.


Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New … from the drop-down menu. Assign the name exercise_05.db to the new database by clicking in the New Database Name box and entering exercise_05 (.db will automatically be appended). Select OK to create the new database. File New... New Database Name

exercise_05

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 5-4



WORKSHOP 5

2.

Import Pro/ENGINEER primitive geometry from a file named oventab.geo.

Select File from the Menu Bar and select Import… from the drop-down menu. Change the Object, Source, and File Type list boxes as shown below. It may be necessary to select a path and use the Filter button to locate the oventab.geo file which should be contained in your home directory.

Import CAD geometry

File Import... Object

Model

Source

Pro/ENGINEER

File Type

Primitive Geometry

Pro/ENGINEER Files

oventab.geo

Apply The model geometry will be imported. A Pro/ENGINEER Model Import form will provide statistics on the entity type and quantity imported. Click OK to close this form.

Summary

OK The display should appear as shown below.


5-5

Import CAD geometry

Select Viewing from the Menu Bar or use the Tool Bar Iso 1 View con to change to an isometric_view. Preference Graphics... Auto Fit View

Apply Cancel Viewing Named View Options... Select Named View

isometric_view

Close Or, use the Tool Bar Iso 1 View Icon.

The model should appear as shown below.

Y Z

5-6

X


WORKSHOP 5

3.

Thermal Analysis using Imported Geometry Create a B-rep solid from these surfaces and delete the original surfaces in the process.

Create a Brep solid

Select the Geometry Applications radio button. Create a B-rep solid using the following Action, Object, and Method.

◆ Geometry Create/Solid/B-rep Delete Original Surfaces Auto Execute Surface List

Apply A message window will request confirmation of deletion. Select Yes. Yes B-rep solid 1 is displayed as white in the viewport.

4.

Mesh the solid with the TetMesh Mesher using Tet4 elements, a global edge length of 2.5.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Solid. The Isomesh Mesher is used on regular parametric solids. In order to mesh this B-rep solid use the TetMesh Mesher. Use the default Tet4 topology and adjust the Global Edge Length and TetMesh Parameters to reduce the mesh resolution for this analysis.

TetMesh the B-rep solid

◆ Finite Elements Create/Mesh/Solid Global Edge Length

2.5

Mesher

◆ TetMesh

Input List

Add Apply

5-8



WORKSHOP 5

6.

Create a boundary sink node 999 below the mounting boss and not associated with geometry.

Select the Finite Elements Applications radio button. Create a boundary node which is not associated with geometry. The node is numbered 999. Locate the node at [0 -5 0] centered below the mounting boss.

Create a boundary sink node

◆ Finite Elements Create/Node/Edit Node ID List

999

Associate with Geometry Node Location List

[0 -5 0]

Apply

7.

Increase node display size and change the view to a Y-Z, side_view. Rotate the view to show the bottom surface of the mounting boss.

Increase the display size of nodes to facilitate the application of boundary condition. Use either Display/Finite Elements... or the associated Tool Bar icon to change the node size.

Increase node size and change to

Display Finite Elements... Node Size (use slider bar)

6

Apply Cancel Select Viewing from the Menu Bar to change to a side_view of the model. Alternately, this step can be completed using the Tool Bar Right Side View icon. Viewing Named View Options... Select Named View

side_view

Close


5-9

Increase node size and change to a Y-Z view

Using Viewing/Transformations... from the drop down menu to change the view point by tilting the 15o around the -Z axis to show the bottom surface of the mounting boss. Viewing Transformations... Options... Rotation increment (deg)

15

OK

Select Nodes

Add OK Apply In order to facilitate applying the next two boundary conditions change the display. Select Display then Entity Color/Label/Render ... Change Render Style to Shaded/Flat or use the Tool Bar Smooth Shaded icon to affect the change. Display Entity Color/Label/Render... Render Style

Shaded/Flat

Apply Cancel


5-11

Fix nodal boundary temperature

The display should appear as shown below. The lower contact edge of the spring tab, and the bottom of the mounting boss should now be visible.

Lower spring tab edge Bottom of mounting boss

Apply the fixed edge temperature. Enter a New Set Name Edge with a fixed temperature of 300.0oC applied to lower edge of the spring tab. New Set Name

Edge

Input Data... Fixed Temperature

300.0

OK Select Application Region...

◆ Geometry Select Geometry Entities

OK Select Application Region... In the Select Applications Region form select the bottom face of the mounting boss. When selecting the surface the surface chosen will be highlighted. If the incorrect surface is selected simply reselect closer to the centroidal location of the bottom mounting boss surface. The centroid is located between the mounting holes and centered on the width of the surface.

◆Geometry Select Solid Faces

Apply Use Show Label icon to display labels.

Complete the fin by transforming the newly created Surface 2. Note that the Repeat Count is adjusted to 3 to create the full fin length.

◆ Geometry Transform/Surface/Translate Translation Vector

<1 0 0>

Repeat Count

3

Surface List

Add OK Apply Create the heat transfer coefficient boundary conditions with the Template, Convection option, set name Air, and a heat transfer coefficient of 2.0 Btu/ oF-hr-ft2. Apply the boundary condition to the exposed edges of both finned heat sinks as shown in Figure1. The same boundary condition is applied to both heat sink models.

◆ Loads/BCs Create/Convection/Element Uniform Option:

Template, Convection

New Set Name

Air

Target Element Type

2D

Input Data... In the Input Data form provide the heat transfer coefficient and fluid node. Convection Coefficient

2.0

Fluid Node ID

Apply The model will appear as shown below.


7-7

IsoMesh the surfaces

3.


Mesh surfaces with an IsoMesh, global edge length of 0.003.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.003 and select both surfaces for inclusion in the Surface List.

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.003

Surface List

Apply Turn off labels using Hide Labels icon.

Create an ambient node

4.

Create two fluid nodes 9998 and 9999 for the oven interior and ambient conditions respectively.

Using the Finite Elements form create a boundary nodes which are not associated with geometry. The node numbers are 9998 and 9999. Locate the nodes at [-0.03 0 0] and [0.11 0 0], to the left and right of model. The spatial location of the boundary nodes is irrelevant to the analysis; but, these locations facilitate display and verification of LBC’s.


9998


[ -0.03 0 0]

Apply Node Location List

[0.11 0 0]

Apply

7-8


WORKSHOP 7

An Oven Window Design

Increase the display size of nodes to facilitate the application of boundary condition. Use either Display/Finite Elements or the associated Toolbar Node Size icon to change the node size. The model should now appear as shown below. Display Finite Elements... Node Size

6

Apply Cancel or,

The display should now appear as shown below.


7-9

Equivalence nodes

5.

Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action, Object, and Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.

Equivalen ce nodes

◆ Finite Elements Equivalence/All/Tolerance Cube Apply 6.

Define the two material properties for the plastics.

Since this will be a steady state analysis, thermal conductivity is the only material property used in the solution. Thermal conductivity values are provided in Figure 1; however, the Input Options form also requires data for Density and Specific Heat. Enter a value of 1.0 in each of these fields. The Apply button is selected from within the Input Options form. The form does not close upon hitting Apply. This is a convenient, if unintended, feature since one needs only to enter a new material name in Material Name and proceed with entering new material data in the Input Options form. After each Apply the new material should appear in the Existing Materials list box on the Materials form.

◆ Materials Create/Isotropic/Manual Input Material Name

ka

Input Properties... Thermal Conductivity =

0.130

Density =

1.0

Specific Heat =

1.0

OK Apply

7-10

Material Name

kb

Thermal Conductivity =

0.07

Density =

1.0

Specific Heat =

1.0


Define two materials


WORKSHOP 7

OK Apply 7.

Apply element properties to the elements using the defined materials. These are Thermal 2D elements.


Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal 2D. Enter Property Set Name interior_pane. Select the Input Properties... box. Click in the Material Name box and select ka from the Material Property Sets list box. Select OK to close the form.Click in the Select Members box and choose Surface 1 from the default viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal 2D Property Set Name

interior_pane

Input Properties... Material Name

Add Apply Perform the same steps for Surface 2 using, exterior_pane, for the Property Set Name, and select kb for the Material Name from the Material Property Sets list box.


exterior_pane


Add MSC.Patran 312 Exercise Workbook - Release 2001

7-11

Create a spatial field

Apply 8.

Define the temperature distribution at the interior pane upper edge.

Select the Fields Applications radio button. Set the Action, Object, and Method to Create/Spatial/Tabular Input. Enter Field Name edge_T. Select Input Data... and enter 2 data pairs 0.0, 345.0 and 0.05, 38.0 via the Input Scalar Data box. Select OK and Apply to finish the definition.

Create a spatial field

◆ Fields Create/Spatial/Tabular Input edge_T

Field Name:

Input Data... Data:

Input Scalar Data:

345.0

Input Scalar Data:

38.0

OK Apply

9.

Apply temperature and conditions.

convection

boundary

Begin applying boundary conditions. Select the Loads/BCs Applications radio button. Create a fixed 345oC nodal boundary temperature named oven. In the Input Data form define the fixed temperature. In the Select Applications Region form pick node 9998 located to the left of the window.

◆ Loads/BCs Create/Temperature/Nodal

7-12

Option:

Fixed

New Set Name

oven


Apply boundary conditions

WORKSHOP 7


Input Data... 345.0

Fixed Temperature

OK Select Application Region... Geometry Filter

◆ FEM

Select Nodes

Add OK Apply Repeat steps for fixed edge temperature distribution using spatial field edge_T. Apply the distribution to the upper Geometry edge of the interior pane. New Set Name

edge

Input Data... Select Spatial Field... Fixed Temperature

Add OK Apply Create the heat transfer coefficient boundary conditions with the Template, Convection option, set name oven_convection, and a heat transfer coefficient of 16.0 W/oC-m2. Apply the boundary condition to the left most oven window surface(edge) as shown in Figure1 with fluid node 9998.



New Set Name

oven_convection

Target Element Type

2D

Input Data... In the Input Data form provide the heat transfer coefficient and fluid node. Convection Coefficient

16.0

Fluid Node ID

Add OK Apply

Repeat these steps for a New Set Name air_convection with a heat transfer coefficient of 13.0 W/oC-m2 applied to the right most oven window surface(edge) as shown in Figure 1 with fluid node 9999. New Set Name

air_convection

Target Element Type

2D

Input Data... Convection Coefficient

13.0

Fluid Node ID

Add OK Apply


7-15

Use Shareware to verify LBC’s

With boundary conditions applied the model should appear as shown below.

Use Shareware to verify LBC’s

10. Visualize and verify the convection LBC’s using Utilities/ Thermal Tools/Thermal BC Display... Shareware contains various utilities for facilitating model creation and LBC’s verification. Verify your convective coupling by drawing a vector from the centroid of each element to the associated fluid node using Utilities/ Thermal/Thermal BC Display... Utilities Thermal Thermal BC Display... OK Apply

7-16


WORKSHOP 7


The model should appear as shown below.

Use Clear and Close in the Thermal BC’s form to revert to a normal display. Clear Close Reduce the node size using the Node Size icon.

11. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

Prepare and run analysis

◆ Analysis Analyze/Full Model/Full Run MSC.Patran 312 Exercise Workbook - Release 2001

7-17

Read and plot results

Translation Parameters... Model Dimensionality

◆ 2D Plane Geometry, XY Co-ordinates (unit Thickness in Z)

OK Solution Parameters... Calculation Temperature Scale

◆ Celsius

Solver Option

1, Weakly Nonlinear Solution

OK Output Requests... Units Scale for Output Temperatures

◆ Celsius

OK Apply


12. Read results file and plot results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_07.db database. Applying the analysis created a new subdirectory with the same name as the Job Name; exercise_07/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_07

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

7-18

pthermal_1_nodal.res_tmpl


WORKSHOP 7


OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Case

TIME: 0.0000000000D+00 S...

Select Fringe Results

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise. What is the exterior temperature of the oven window? Is it at or below the required maximum of 50oC?

13. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.


Quit MSC.Patr

7-19

Quit MSC.Patran

7-20


WORKSHOP 8

Temperature Dependent Material Properties

Objective: ■

You will create a 2D material slice consisting of two materials with temperature dependent material properties.

■

You will visually and qualitatively compare the MSC/ THERMAL results with the results of an analytical solution.


8-1

8-2



WORKSHOP 8

Model Description: In this exercise you will learn to create temperature dependent material properties. There are very few analytical solutions available for composite materials with temperature dependent conductivities. Recently, K. C. Chang and V. J. Payne published an analytic solution for the problem you will analyze in this exercise (Journal of Heat Transfer, Feb. 1991, Vol. 113, pp. 237). Results of their work have been included at the end of this exercise to allow you to qualitatively compare your solution to theirs.

Material 1

Material 2 T = 100OC = 373.2 K

T = 600OC = 873.2 K

Ta = 0O C = 273.2 K

0.5 X 0.5 Dimension K1= K10 (1 + α1 Τ) K2 = K20 (1 +α2 Τ)

.

K10 = 0.060

α1 = 0.0006

K20 = 0.001

α2 = 0.00001


8-3

Create a new database


Create a new database named exercise_08.db. Set the Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create two surfaces which model the two adjoining material slabs.

■

Mesh the surfaces with an IsoMesh.

■

Identify “cracks” in the model and Equivalence the nodes at the mating surface edges.

■

Define the two materials using Fields/Create/ Material Property/General.

■

Using the fields just defined create Material 1 and Material 2.

■

Apply element properties to the elements referencing the two material properties just defined.

■

Apply the three temperature boundary conditions to the edges of your model.

■

Prioritize temperature boundary conditions at the lower corners.

■

Prepare and submit the model for analysis.

■

Read results file and plot results.

■

Compare the results to the analytical solution.

■

Quit MSC.Patran.

Exercise Procedure: Create a new database

1.

Create a new database named exercise_08.db. Set the Tolerance to Default, and the Analysis Code to MSC/THERMAL.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar Menu Bar and select New… from the drop-down menu.

8-4



WORKSHOP 8

Assign the name exercise_08.db to the new database by clicking in the New Database Name box and entering exercise_08 (.db will automatically be appended). Select OK to create the new database. MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. 2.

Create two surfaces which model the two adjoining material slabs.

Select the Geometry Applications radio button. Set the Action, Object, and Method to Create/Surface/XYZ. Change the Vector Coordinates List to <0.5, 0.5, 0> and click on the Apply button to create the first patch

Create the two material

Change the Origin Coordinates List to [0.5, 0, 0], and click on the Apply button to create the second surface.

Y Z

X


8-5

IsoMesh both surfaces

3.

IsoMesh both surfaces

Mesh the surfaces with an IsoMesh.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Set the Global Edge Length to 0.025. Click in the Surface List box and drag a rectangle around both surfaces. Select Apply to complete the meshing function. The completed form and resulting display are shown below. Finite Elements Action: Object:

Type:

Create Mesh Surface

Output IDs Node ID List 1 Element ID List 1 Global Edge Length 0.025 Element Topology Quad4 Quad5 Quad8 Mesher

◆Paver ◆IsoMesh◆ IsoMesh Parameters... Y

Node Coordinate Frames... Z

Surface List Surface 1 2

X

-Apply-

The display should appear as shown above. If it does not, select the undo icon and analyze the error to a resolution.

Equivalen ce mesh nodes

4.

Identify “cracks” in the model and equivalence the nodes at the mating surface edges.

In the Finite Elements form set the Action, Object, and Test to Verify/Element/Boundaries. Select Apply. In the Finite Elements form set the Action, Object, and Method to Equivalence/All/Tolerance Cube. Select Apply to complete the function. Verify element boundaries again. 8-6



WORKSHOP 8

The nodes bounding the interior edges will be circled in the display and the Command Window will indicate that a number of nodes are deleted. All gaps or cracks have now been eliminated from the mesh. 5.

Define the two materials using Fields/Create/ Material Property/General.

Select the Fields Applications radio button. Set the Action, Object, and Method to Create/Material Property/ General.

Define the material property fields

Enter a Field Name K2 and select Input Data... In the General Field Input Data form Select Function Term mpid_arbt_plyn. General Field Input Data Select Function Term: Function Term Type:

P3 Functions

Term Sub-Type: MSC/THERMAL Matl Func Select Function Term: mpid_arbt_plyn mpid_bghm mpid_cnst

Function Expression

Modify Highlighted Function OK

An Arbitrary Order Polynomial form will be displayed. On this form, change the Temperature Units option menu to Kelvin. Then enter Coefficient Data for Material K2 conductivity, (K2 = 0.001 + 0.00000001 T). First enter 0.001 in the Coefficient,A(Index) followed by a carriage return. Next enter 1.0E-8 followed by a carriage return. Before completing this form enter a description in the Description entry box.


8-7

Define the material property fields

The form should appear as shown below. Arbitrary Order Polynomial Define Material Property: Arbitrary Order Polynomial P(X) = A(1) + A(2)*X + ... A(n)*X**(n-1) Note: The temperature scale only indicates the valid units. ICCALC units will be used in the evaluation. Select Existing Table... Build Arbitrary Order Polynomial Table Description - Arbitrary Order Polynomial Table

Material K2 Material Property ID (MPID) 100001

Scale Factor 1.0

Independent Variable Type Temperature

Temperature Units Kelvin

Input Coefficient, A(I) Value Coefficient, A(I) 1

0.001

2

9.99999999E-09

3 4

Clear Selected cell(s) Number of Rows to Insert OK

Delete selected row (s) 1 Defaults

Insert row(s) Cancel

Select OK in the Arbitrary Order Polynomial form. Select OK in the General Field Input Data form. Select Apply button on the Fields form to complete the function. In the Field form change Field Name to K1. Again choose the mpid_arbt_plyn. Click on the Coefficient 1 cell in the Coefficient Data frame and enter the Coefficient,A(Index) data for the thermal conductivity of Material 1, (K1 = 0.06 + 0.000036T). Change the Temperature units to Kelvin and add a description in the Description entry box.

8-8



WORKSHOP 8

6.

Using the fields just defined create Material 1 and Material 2.

Select the Materials Applications radio button. Set the Action, Object, and Method to Create/Isotropic/Manual Input. Enter Material_1 in the Material Name databox. Select Input Properties... In the Input Options form click into the Thermal Conductivity data box.

Define material properties

The form should be modified to include a Time, Temperature, or Constant Fields: list box. Select K1 from the listbox. Enter unit values for Density and Specific Heat. Input Options Thermal properties

Constitutive Model Property Name

Value

Thermal Conductivity

K1

Density

1.0

Specific Heat

1.0

Phase change temperature Latent Heat

Time, Temperature or Constant Fields: K1 K2

Repeat the same procedure for Material_2; this time selecting K2 for Thermal Conductivity. After creating both materials select Cancel to close the Input Options form 7.

Apply element properties to the elements selecting the two material properties just defined. Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal 2D. Enter Property Set Name Prop1. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and select Material_1 from the Material Properties Sets list. Select OK to close the form. Click in the Select Members box and select Surface 1, the left surface. Select Add then Apply in the Element Properties form to complete the element property definition for Surface 1. MSC.Patran 312 Exercise Workbook - Release 2001


8-9

Apply boundary temperatures to 3 edges

Perform the same steps for Surface 2, the right surface, using Prop2, for the Property Set Name, and Material_2 for the Material Name. 8.

Apply boundary temperature s to 3 edges

You will now apply the three temperature boundary conditions to the edges of your model.

Left vertical edge of Surface 1: Select the Loads/BCs Applications radio button. Set the Action, Object, and Type to Create/Temperature (PThermal)/Nodal with an Option: of Fixed. Enter the name, Mat1_Edge_Temp, into the New Set Name data box. Click on the Input Data... button and enter a Fixed Temperature of 873.2. Click on the OK button to close the Input Data form. Select the Select Application Region... button and set the Geometry Filter to Geometry. Click on the Select Geometry Entities box, select the Curve or Edge icon in the Select Menu. Select the left-hand vertical edge of Surface 1. Select Add then OK to affect and close the Select Application Region form. The completed forms are shown below. Input Data

Load/Boundary Conditions Create

Action:

Object: Temperature(PThermal)

Option:

Select Spatial Field...

Fixed

Analysis Type:

Application Region

Thermal

Default...

Select Geometry Entities

Reset

Current Load Case:

Type:

Geometry Filter Geometry FEM

Fixed Temperature 873.2

Nodal

Type:

Select Application Region

OK

Static

Existing Sets

Cancel Add

Remove

Application Region Surface 1.1

New Set Name Mat1_Edge_Temp

Input Data... 8-10


OK

WORKSHOP 8

Temperature Dependent Material Properties Select Apply to create the temperature boundary condition. Perform similar steps to assign the remaining temperature boundary conditions to your model. Use the following New Set Name, and Fixed Temperature values. New Set Name

Fixed Temp

Mat1_2_Bottom_Edge_Temp Mat2_Edge_Temp

273.2 373.2

Your model should now look like the one shown below.

Applying the temperature boundary conditions to the various edges of your model created a conflict at the two lower corner points. At the lower left corner both the 873.2 and 273.2 temperature boundary conditions were applied. At the lower right corner both the 373.2 and 273.2 temperature boundary conditions were applied. By default MSC/PATRAN adds overlapping boundary conditions. To fix the lower corner temperature to 273.2 you must tell MSC/PATRAN that the boundary condition you applied to the bottom edge of the model has priority over the conflicting vertical edge boundary conditions.


8-11

Prioritize temperature BC’s

Prioritize temperatur e BC’s

9.

Prioritize temperature boundary conditions at the lower corners.

Select the Load Cases Applications radio button.Change the Action: to Modify. In the Load Cases form highlight the Default load case in the Existing Load Cases list box, if necessary. Select the Priority cell for LBC 1, Mat1_2_Bottom_Edge_Temp. Select the Value button. A value of 1 should appear in the Priority cell. Select the Mat1_Edge_Temp LBC then again set the Priority to 2 using the Value cell. Repeat for the last LBC, Mat2_Edge_Temp. The completed forms are shown below.

Select OK in the Prioritize Load/BCs form and Apply in the form. If the Message box, “Do you wish to overwrite?” appears, answer Yes.

Load Cases

8-12


WORKSHOP 8


10. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select Translation Parameters... Select the 2D Plane Geometry,XY Co-ordinates (Unit Thickness in Z) radio button in Model Dimensionality. Select OK to close the P/ Thermal Translation Parameters form.


Select Solution Parameters... Select the Kelvin radio button in Calculation Temperature Scale. Select OK to close the P/Thermal Solution Parameters form. Select Output Requests... Select the Celsius radio button in Unit Scale for Output Temperatures. Select OK to close the P/Thermal Output Requests form. Since all other defaults are acceptable submit the analysis by selecting Apply in the Analysis form From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. 11. Read results file and plot results. Recall that p3 was initiated from a working directory which contained the excercise_08.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_08/. By using Read Result in the Analysis form and Select Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file


Select the nr0.nrf.01 results file in the Available Files list box. Select OK. Select the Select Rslt Template File....in the Analysis form. In the Template to Import P/THERMAL Nodal Results form select the template named pthermal_1_nodal.res_tmpl from the Files list. Select OK. Select Apply in the Analysis form to read the chosen results file with the selected template.


8-13


To plot the results use the Results Application radio button. The default Action/Object should be Create/ Quick Plot. Select Fringe Result: Temperature. Hit Apply to quick plot the default Result Case and Fringe Result. To affect a better comparision use the Fringe Attributes icon to change the display and range. Select Display: Element Edges. Select Label/Style... Under Label/Style... select Label/Format: Fixed and use the slider bar to select 4 Significant figures, then select OK, and Apply. Select Range.../Define Range.../Create... Use a new Range Name: Compare with Number of Sub-Ranges: 7. Select OK. In the Range form select Data Method/From. In the spread sheet at the bottom of the form, select the 0th cell in the From column. In the Spreadsheet Input data line, type 600.0 and carriage return. Move to the next cell down and repeat these steps for 500, 400, 300, 200, 110, and 50. Select Calculate. Hit Apply. Finally select Assign Target Range to Viewport. Close all the sub-forms and click Apply on the Results form.

8-14



WORKSHOP 8

12. Compare the results to the analytical solution.

Compare results

Shown below is the temperature contours derived by K. C. Chang and V. J. Payne.

: temperature-independent : temperature-dependent material 2

110

300

400

500

0.4

interface 200

material 1

0.5

0.3 0.2

50

0.1 0.0 0.0

0.1

13.

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Quit MSC.Patran.

Select File on the Menu Bar and select Quit from the dropdown menu.


Quit MSC.Patr

8-15

Quit MSC.Patran

8-16


WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

Objective: ■

In this exercise you complete a steady state thermal analysis of the 3D hybrid microcircuit.


9-1

9-2


WORKSHOP 9


Model Description: In this exercise complete the analysis of a hybrid microcircuit which is subjected to a bench functional test. The hybrid is clamped to a test fixture which is chilled by iced water. The microcircuit is continuously flushed by a dry nitrogen purge at 21oC. During functional testing, which takes approximately 1 hour, the entire hybrid dissipates 8 watts. Each device dissipates a constant wattage, as listed. The goal of the analysis is to verify that all device temperature shall remain below 50oC.



■

Use Finite Elements/Create/Node/Edit to create the two fixed temperature boundary nodes.

■

With Display/Finite Elements... or the equivalent Tool Bar function increase the display size of nodes to facilitate boundary definition.

■

Use Loads/BCs/Create/Temperature/Nodal with Option: Fixed to set the boundary node temperatures.

■

Use Loads/BCs/Create/Convection with Option: Fixed Coefficient to apply the contact and nitrogen flow heat transfer coefficients.

■

Post only the device_and_solder group and use the middle mouse button or various Viewing functions to expose the individual device surfaces.

■

Use. Loads/BCs/Create/Heating with Option: Template, Volumetric Heat to apply the heating load to the individual devices.

■

Select Analysis to prepare and to submit the model for analysis and to Read Results.

■

Post hybrid_fem, select an isometric_view, select Results, and review results data.

■

Quit MSC.Patran.


9-3

Hybrid microcircuit boundary conditions

Hybrid microcircu it boundary conditions

Figure 1-Boundary Conditions h=8 w/m2-oC

h=1000 w/m2-oC

Nitrogen Flow Node 9998 21oC

Cold Plate Node 9999 0oC

Figure 2-Device Position 0.50w R1 1.00w R3

0.75w R2 0.25w R4 Total 8.00 watts

3.00w 0.50w 1.50 w 0.50w V4 V2 V3 V1

Table 2-Device Heat Generation

9-4

3

Device R1 R2 R3 R4

w/m 0.167E+09 0.250E+09 0.333E+09 0.083E+09

V1 V2 V3 V4

1.500E+09 0.250E+09 0.750E+09 0.250E+09



WORKSHOP 9



Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window.


Next, select File from the Menu Bar and open the existing microcircuit database. File Open... Database List

microcircuit.db

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. 2.

Create the two fixed temperature boundary nodes.

Select Viewing from the Menu Bar or use the Tool Bar Right Side View icon to change to a side_view of the model hybrid_fem entities.

Create 2 boundary nodes

Viewing Named View Options... Select Named View

side_view

Close Select the Finite Elements Applications radio button. Create two nodes which are not associated with geometry. The first node is numbered 9998.


9998


[0.01 0.01 0.002]

Apply


9-5

Change display and picking preferences

The second node is numbered 9999.


9999


[0.01 0.01 -0.007]

Apply

3.

Change display and picking

Increase the display size of nodes and picking preferences to facilitate boundary definition.

Increase the display size of nodes and modify the Picking Preferences to facilitate the application of boundary condition. Use either Display/Finite Element/Node Size or the associated Tool Bar icon to change the node size. Display Finite Elements... Node Size (Use Slider Bar)

6

Apply Cancel And, select Preference/Picking... to change the Rectangle/Polygon picking method to Enclose Centroid. Preferences Picking...

◆ Enclose Centroid Close Select Display/ Load/BC/Element Props /Vectors... to facilitate viewing boundary conditions. Display Load/BC/Elem. Props... Show LBC/El. Prop Values

9-6


WORKSHOP 9


Vectors/Filters... 0.05

Scale Factors:

Apply Cancel Apply Cancel 4.

Fix the boundary node temperatures.

Begin applying boundary conditions. Select the Loads/BCs Applications radio button.Create a fixed temperature boundary named Cold_plate.

Fix nodal boundary temperature

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

Cold_plate

Input Data... In the Input Data form define the fixed temperature. 0.0

Fixed Temperature

OK Select Application Region... In the Select Applications Region form pick node 9999.

◆ FEM Select Nodes

Add OK Apply The display should highlight each node and append the fixed temperature. On some displays the symbol and value may be difficult to discern.

Apply convectio n boundary

5.

Apply contact and nitrogen flow heat transfer coefficients.

Create two convective boundary conditions with the Use Correlations option and the heat transfer coefficients provided in Figure 1. Name the first set nitrogen_flow and apply the boundary condition to all of the element free faces on the top and sides of hybrid_fem.


Fixed Coefficient

New Set Name

nitrogen_flow

Target Element Type

3D

Region 2

Nodal

Input Data... In the Input Data form provide the convection coefficient and fluid node association. Convection Coefficient

8.0

OK Select Application Region... 9-8


WORKSHOP 9


In the Select Applications Region form select all the free faces of the top and sides of the model. Exclude the bottom of the model by not enclosing it in the dragged rectangle.

◆ FEM Application Region / Select 3D Element Faces

Add OK Apply

Y

Z

X


9-9

Apply convection boundary conditions

Repeat this process for a New Set Name heat_sink with a convection coefficient of 1000.0 applied to the bottom surface of the hybrid_fem. heat_sink

New Set Name


1000.0


◆ FEM Application Region / Select 3D Element Faces

Add OK Apply

Y

Z 9-10

X



WORKSHOP 9

6.

Post only the device_and_solder group and rotate to a view which shows the top device elements

Post only device_an d_solder

Select Group/Post... and Reset Graphics to facilitate applying volumetric heat loads. Group Post... Select Groups to Post

device_and_solder

Apply Cancel Reset Graphics

Select Viewing from the Menu Bar or use the Tool Bar Iso 1 View icon to change to a isometric_view of the device_fem entities. Viewing Named View Options... Select Named View

isometric_view

Close 7.

Apply device volumetric heat loads.

Apply device volumetric heat loads

Based on the data in Table 2 apply volumetric heat loads to R1 through V4, the surface mounted components. The heat load should be placed only on the top layer of elements, the silicon devices.

◆ Loads/BCs Create/Heating/Element Uniform Option:

Template, Volumetric Heat

New Set Name

R1

Target Element Type

3D

Input Data... MSC.Patran 312 Exercise Workbook - Release 2001

9-11

Apply device volumetric heat loads

Vol Heat Generation

0.167E+09


◆ FEM Select 3D Elements

Select Members

Add Apply

5.

Create 2 time dependent microfunctions using Fields and Create/Non Spatial/General.

Microfunctions are created in the Fields form using the Action/Object/ Method Create/Non Spatial/General. After selecting Input Data. The General Field Input Data form will show the complete list of microfunctions in the Select Function Term: list box.

Create microfunctions

Figure 1 contains the data required for entry into the various microfunction forms. The entries and selection below will guide you through the process of creating the microfunctions. An image of each completed microfunction form is included to facilitate microfunction entry.

◆ Fields Create/Non Spatial/General Field Name

Tsine MSC.Patran 312 Exercise Workbook - Release 2001

10-7

Create micro-functions

Input Data... Select Function Term

mfid_sine_wave

Micro Function ID

11

P1 Value

15.0

P2 Value

0.034907

P3 Value

4.71239

P4 Value

115.0

OK OK Apply The Micro Function form should appear as shown below. Micro Function: Sine Wave Define Micro Function Option 3 Sine Wave F(X) = P1 * SIN(P2 * X + P3) + P4 Micro Function ID (MFID) 11

Micro Function Option 3

Micro Function Description

Independent Variable Type Time P1 Value 15

P2 Value 0.034907

P3 Value 4.712389

P4 Value 115.0

OK

10-8

Reciprocal Micro Function

Defaults


Cancel

WORKSHOP 10

Time Dependent Boundary Conditions

Tflip_flop

Field Name

Input Data... Select Function Term

mfid_flip_flop

Micro Function ID

121

P1 Value

60.0

P2 Value

180.0

P3 Value

150.0

P4 Value

100.0

OK OK Apply The Micro Function form should appear as shown below. Micro Function: Flip Flop Function Define Micro Function Option 15 Flip Flop Function If P1<= X < P2, Then F(X) = P3 Else F(X) = P4 Microfunction ID (MFID)

Microfunction Option

121

15

Microfunction Description

Independent Variable Type

Reciprocal Microfunction

Time P1 Value

P2 Value

60.0

180.0

P3 Value

P4 Value

150.0

100.0

OK

Defaults

Cancel


10-9


6.


Define 4 temperature boundary condition in Loads/ BCs, 1 fixed nodal temperature in the lower left corner of the plate and 3 variable nodal temperatures on the remaining corners.

Begin applying boundary conditions. Select the Loads/BCs Applications radio button. Create a fixed 100oC nodal boundary temperature named T1. In the Input Data form define the fixed temperature. In the Select Applications Region form pick Node 1 located in the lower left corner of the plate.


Fixed

New Set Name

T1


100.0


◆ FEM

Select Nodes

Select Nodes

Add OK Apply Repeat these steps for New Set Name T121 with Template ID 3 on Node 121. T121

New Set Name

Input Data... 3

Template ID


Add OK Apply With boundary conditions applied the model should appear as shown below

10-12



WORKSHOP 10

7.

Use the new Analysis/Build Template to create the MACRO definitions in the template.dat.apnd file.

Beginning with MSC.Patran THERMAL V8, the template.dat.apnd file can be created from within the MSC.Patran interface. The ANALYSIS/BUILD TEMPLATE forms allow creating and editing all of the required templates.

Create template.d at.apnd file

Use the following chart to help you define the MACRO functions for the temperature boundary conditions assigned to Nodes 11 and 121. Table 1: TID#

Node 1

Node 2

scale_factor

mfid#

2

0

0

1

11

3

0

0

1

121

Note: Nodes 1 and 2 are set to zero since the argument is time.

◆ Analysis Build Template Create Template File... Create/MACRO/Data Entry MACRO ID

2

MFID’s

11

Apply A Template Entries form will appear, close it. Cancel MACRO ID

3

MFID’s

121

Apply Write File...


10-13


In the File Option form, template.dat.apnd should be the default name in the File Name input box. OK Cancel Cancel Shown below is the final form of the template.dat.apnd file created for this exercise. MACRO 2 1 0 0 1.0 11 MACRO 3 1 0 0 1.0 121

8.



Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

◆ Analysis Analyze/Full Model/Full Run Solution Type... Select Thermal Solution

◆ 1, Transient Run


◆ Celsius

Run Control Parameters... Stop Time

360.0

Initial Temperature =

100.0

OK OK Output Requests... Units Scale for Output Temperatures

10-14

◆ Celsius



WORKSHOP 10

Print Interval Controls... Initial Print Interval

30.0

OK OK Apply

9.

Read the results files using Utilities and plot results for several time steps. Do not delete the database from your directory since it will be used in a future exercise.


From within MSC.Patran the only indication that the analysis has successfully finished is the existence of nrX.nrf.01 (“x” will range from 112) results files in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_010.db database. Applying the analysis created a new subdirectory with the same name as the Job Name, exercise_10/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file Utilities provides a results reader under Thermal which facilitates reading the results of transient runs. If you do not have Shareware installed or is unavailable then skip to the instructions below which tell you how to read the results from the Analysis form. Utilities Thermal Thermal Results Reader... Disclaimer

OK Directories

/exercise_10

Filter All your nr.nrf.01 files should appear in the Selected Files list box. Edit the end of the path and file in the Selected File box to end in nr*. Selected File

/exercise_10/nr*


10-15


OK Apply All the files will be read into the database. Since the analysis does not involve convection template ID’s, the results template that is used in reading the files detects that there are no such entries and creates a warning message for each occurrence. This warning is irrelevant to this analysis. When the warning messages cease. Click OK in the Warning form. Select Close to exit the Utilities. Warning

OK Close [OPTIONAL METHOD follows. Use only if necessary] If for whatever reason Utilities are unavailable you can use the standard MSC.Patran method of reading the results files. However, a Global Variable for Time will not be created in the Result Cases. This will adversely affect the animation subsequently created in Exercise 19.


/exercise_10


nr0.nrf.01



OK Apply Once you have selected a Results Template you can repeat the Select Results File... step and hit Apply on the Read Results form without again selecting a template. Select Results File... 10-16


WORKSHOP 10


Available Files

nr1.nrf.01

OK Apply Repeat these steps for each nr#.nrf.01 file until all results are read. [END OPTIONAL METHOD] After results are read in by either method, plot the results. To plot the results use the Results Application radio button. Select results for t=150s.

◆ Results Create/Quick Plot Select Result Cases

TIME: 1.5000000000D+02 S...

Select Fringe Result

Temperature,


Display:

Element Edges


Fixed

Significant figures

4

OK Apply The posted results are for t=150s. The model should now appear as shown on the front panel of this exercise. Feel free to post results from other times to verify your results. Do not delete the database when you finish this exercise it will be used in a future exercise. In that exercise we will animate the results to display the model’s behavior through time. 10. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu. MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr 10-17

Quit MSC.Patran

10-18


WORKSHOP 11

Using Convection Correlations

Objective: ■

Model an iron cube.

■

Apply convective boundary conditions using correlations from the MSC.Thermal convection correlation library.

■

Run a steady state analysis and display results.


11-1

11-2


WORKSHOP 11


Model Description: In this exercise you will determine the steady state temperature distribution in an iron cube (MID 18). The temperature distribution will be driven by a heat flux on one vertical face, natural convection on another vertical face, and forced convection on the top horizontal face. CONV definitions link convection Template ID’s (TID’s) which are applied in the Loads/BC’s form to convection configurations and associated Material Property ID’s (MPID’s). CONV definitions for air will be placed in a mat.dat.apnd which you create using an editor. The mat.dat.apnd file is placed in the same directory as your database. MSC.Patran contains an extensive library of convection coefficient configurations. The configurations are described in Chapter 9, Volume 1 of the MSC.Thermal Application Module User Manual. This volume can be accessed through the on-line Help/Document Library...

Figure 1 Forced Convection T = 300oK V = 10 m/s

Heat flux 1000 W/m2 Iron Cube (MID =18)

Natural convection Tamb = 300oK g = 9.81 m/s2


11-3

Exercise Overview:

11-4

■

Create a new database named exercise_11.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create a 1m x 1m x 1m solid.

■

Mesh the solid with an IsoMesh of Hex8 elements, Global Edge Length of 0.100.

■

Use Finite Elements/Create/Node/Edit to create a boundary node not associated with geometry.

■

Apply element properties to the Hex8 elements defining them as Thermal 3D Solid and having a Material Name (MID) of 18.

■

Create a spatial field which will provide distance-from-theleading-edge data to the convection coefficient calculation.

■

Define a fixed temperature and heat flux boundary condition in Loads/BCs.

■

Define two convection boundary conditions assigning each a different Convection Template ID and supplying the distance from the leading edge in the Convection Coefficient data box.

■

Use the new Analysis/Build Template form to create a template.dat.apnd containing the CONV definitions.

■

In your xterm window (shell) and in the directory which contains the database, use get_qtran to copy an existing file, mat.dat.apnd, containing air MPID data to your directory.

■

Prepare and submit the model for analysis specifying that it is a steady state, that all calculations and output should be oK, and that all eight columns of nodal results are included in the nodal results file.

■

Read and plot the results.

■

Quit MSC.Patran.



WORKSHOP 11



Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window.

Open a new database

Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name exercise_11.db to the new database by clicking in the New Database Name box and entering exercise_11 Select OK to create the new database File New New Database Name

exercise_11

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 2.

Create a 1m x 1m x 1m solid.

Select the Geometry Applications radio button. Create a solid using the following Action, Object, and Method.

Create solid geometry

◆ Geometry Create/Solid/XYZ Vector Coordinate List

<1 1 1 >

Apply


11-5

IsoMesh the solid

Select Viewing from the Menu Bar or use the ToolBar Iso 1 View icon to change to an isometric_view. Viewing Named View Options... Select Named View

isometric_view

Close or,

3.

IsoMesh the solid

Mesh the solid with an IsoMesh of Hex8 elements, Global Edge Length of 0.1.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Solid. For the solid list, select Solid 1.

◆ Finite Elements Create/Mesh/Solid Solid List

Apply The resulting model is shown below.

11-6



WORKSHOP 11

4.

Use Finite Elements Create/Node/Edit to create a boundary node 9999 not associated with geometry.

In the Finite Elements form create a boundary node which is not associated with geometry. The node is numbered 9999. Locate the node at [1.3 1.3 0.5].

Create a boundary sink node

◆ Finite Elements Create/Node/Edit Node ID List Associate with Geometry Node Location List

9999

[1.3 1.3 0.5]

Apply Increase the display size of nodes. Use either Display Finite Element or the associated ToolBar icon to change the node size. Display Finite Elements... Node Size

6

Apply Cancel or,

ToolBar Node size



11-7


5.


Apply element properties to the Hex8’s defining them as Thermal 3D Solid and having a material name (MID) of 18.

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/3D/Thermal 3D Solid. Enter Property Set Name Prop1. Select the Input Properties... box. Click in the Material Name box and enter 18. Select OK to close the form. Click in the Select Members box and select Solid 1 in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/3D/Thermal 3D Solid Property Set Name

Prop1


18

OK Select Members

Add OK Apply


11-9

Create two convection Template ID’s

Create a set name Flux of 1000 W/m2. Apply the boundary condition to the left facing (-X normal) surface of the solid, Solid 1.1, as shown in Figure1.

◆ Loads/BCs Create/Heating/Element Uniform Option:

Flux, Fixed

New Set Name

Flux

Target Element Type

3D

Input Data... 1000

Heat Flux

OK

When selecting a surface, the surface chosen will be highlighted. Hold down the key and use the right mouse button to cycle through surfaces that may overlap or share an edge. Select Application Region... Geometry Filter

◆Geometry

Select Solid Faces

Close Convection Template ID

93

Fluid Node ID

Add OK Apply


11-11

Create two convection Template ID’s

Repeat these steps for a New Set Name natural_convection. Click in the Convection GP2/GP3 data box. Leave the CONV GP2/GP3 blank. Use a Convection Template ID of 913, and a Fluid Node of 9999. In the Select Applications Region form select the right face (+X normal) of Solid 1, (Solid 1.2).

With boundary conditions applied the model should appear as shown below

You may also choose to review your loads and boundary conditions using Utilities/Thermal/Thermal BCs Display. Utilities Thermal Thermal BC Display... A disclaimer message may appear, select OK.. OK Apply 11-12



WORKSHOP 11

Use Clear and Close in the Thermal BC Display form to revert to normal display. Clear Close 9.

Use the new Analysis/Build Template form to create a template.dat.apnd containing the CONV definitions.

Create template.d at.apnd file

Using Analysis/Build Template, create and edit the file template.dat.apnd in the directory which contains your database and where MSC.Patran is running. Use the following table to help you define the convection templates for the forced and natural convection boundary conditions. You should also review the definition of the convection configuration 3 and 13 in the MSC.Thermal USERS MANUAL, Volume 1, Chapter 9. Conv Type

TID#

config#

GP Value

Forced

93

3

10.0

Natural

913

13

1.0, 1.0, 0.0, 9.8

MPID’s (order is important) 550100, 550101, 550103, 550105 550100, 550101, 550106, 550103, 550105

◆ Analysis Build Template Create Template File... Create/CONV/Data Entry CONV ID:

93

CFIG ID

3

Info GP Values

10.0

MPID’s

550100 550101 550103 550105

Apply Cancel CONV ID:

913

CFIG ID

13 MSC.Patran 312 Exercise Workbook - Release 2001

11-13

In unix copy a mat.dat.apnd file

Info GP Values

1.0 1.0 0.0 9.8

MPID’s

550100 550101 550106 550103 550105

Apply Write File... OK Cancel Close

Cancel

Shown below is the final form of the template.dat.apnd file created for this exercise. *================================== CONV 93 3 1 4 10.0 550100 550101 550103 550105 CONV 913 13 4 5 1.0 1.0 0.0 9.8 550100 550101 550106 550103 550105 *==================================

In unix copy a mat.dat.ap nd file

10. In your xterm window (shell) and in the directory which contains the database, use get_qtran to copy an existing file, mat.dat.apnd, containing air MPID data to your directory. Copy a mat.dat.apnd file into the same directory in which you’ve created the template.dat.apnd file. The commands are as follows: > get_qtran

Note: If you receive a “command not found” error then it indicates that you do not have a path to P3.HOME. In this case type: > which p3 (response) > /bin/p3 11-14


WORKSHOP 11


Then type in: > /bin/get_qtran

(response) > Enter a problem directory name or to exit: > prob4 (response) > Enter a filename (* to copy all files) or to exit: > mat.dat.apnd (response) > Copying mat.dat.apnd

A mat.dat.apnd should now reside in your database subdirectory. This file contains more material properties than required. This will not adversely affect the analysis. Feel free to review the format and syntax of the mat.dat.apnd file. You can use this file as a boiler plate for creating your own material properties file data. The template.dat.apnd and mat.dat.apnd files are the only two files that may need to be created outside of the MSC.Patran in order to complete an analysis. As MSC.Patran evolves the creation of this files will be absorbed within the MSC.Patran interface. 11. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.


◆ Analysis Analyze/Full Model/Full Run Translation Parameters... OK Solution Parameters... Run Control Parameters... Initial Temperature =

300.0

Initial Temperature Scale

◆ Kelvin

OK MSC.Patran 312 Exercise Workbook - Release 2001

11-15


OK Output Requests... Units Scale for Output Temperatures

◆ Kelvin

Nodal Results File Format... Select Thermal Entries to Output

Apply

Select Viewing/Scale Factors... to increase the scale of the model in the Ydirection. This will expand the model display to facilitate viewing, picking, and displaying results. Only the model display is scaled not the actual model dimensions. Scaling may throw the coordinate system symbol out of the display viewport. Viewing Scale Factors... Model Y

5.0

Apply Cancel

12-6


Analysis of a Fuel Nozzle Tip

WORKSHOP 12

The resulting model is shown below.

2

3 1

5 2

1

4

6

To create the surfaces that will represent the geometry where the Steel and Still Air will reside set the Geometry form Action, Object, and Method to Transform/Surface/Translate. Click in the Translator Vector databox and then choose the following Tip and base points icon.

Click on Point 5 and Point 6 to define the translation vector. Next, set the Repeat Count to 2, click in the Surface List databox and drag a rectangle around Surface 1 and Surface 2 in the viewport.


Repeat Count

2

Auto Execute Surface List


12-7

Create the nozzle and fluid stream geometry

Apply The resulting model is shown below.

2 1 7

3 1 3 5

10

4 8 11

5 2 4 6

6 9 12

The flow of fuel within the nozzle will be modelled with advection bars. Create the two curves where the bars will be placed. Change the Action, Object, and Method to Create/Curve/XYZ. For the first curve set the Vector and Origin Coordinates List to, <4.5 0 0> and [0 0 0] respectively.

◆ Geometry Create/Curve/XYZ Vector Coordinates List Auto Execute Origin Coordinates List

<4.5 0 0> [0 0 0]

Apply To create the second curve set the Vector and Origin Coordinates List to <0.5, 0, 0> and Point 14 respectively. Vector Coordinates List

<0.5 0 0>

Origin Coordinates List

Apply 5.

Use Finite Elements/Create/Node/Edit to create two ambient nodes 998 and 999 for the ambient and flame temperatures.

In the Finite Elements form create a boundary node which is not associated with geometry. The node is numbered 998. Locate the node at [2.5 0.3 0].

Create boundary nodes


998

Associate with Geometry

Auto Execute

Node Location List

[2.5 0.3 0]


12-13


Apply

Repeat for Node 999 located at [5.2 0.15 0].

Increase the display size of nodes. Use either Display/Finite Elements... or the associated Tool Bar icon to change the node size. Display Finite Elements... Node Size

9

Apply Cancel or,

Select Display/Entity Color/Label/Render.../Hide All Entity Labels or use the Tool Bar Labels Hide icon to remove all labels and unclutter the display. Display Entity Color/Label/Render... Hide All Entity Labels Apply Cancel or,

12-14


WORKSHOP 12



6.


Using the Finite Elements form set the Action/Object/Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.

Equivalen ce nodes


Apply Thermal Axisymmetric element properties to the nozzle and Advection Bar element properties to the flow stream.

Use Tool Bar Label Control icon to turn on Surface labels. Close

Apply element properties to nozzle

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal Axisymmetric. Enter Property Set Name Nickel. Select the Input Properties... box. Click in the Material Name box and enter 243. Select OK to close the form.Click in the Select Members box


12-15

Create fluid nodes and Convective Quads

and select Surfaces 1, 2, and 4 in the viewport using the shift-left mouse button. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal Axisymmetric Nickel

Property Set Name

Input Properties... 243

Material Name

OK

Add Apply The last element property you will create will define the Bar2 elements as advective bars. Change the Dimension to 1D and the Type to Advection Bar. Enter Adv_bars for the Property Set Name and then click on the Input Properties… button. When the Input Properties form appears enter 1 for the Cp-MPID and 50 for the Mass Flow Rate. Create/1D/Advection bar Property Set Name

Adv_bars

Input Properties... [Specific Heat MPID]

1

Mass Flow Rate

50

OK Select Members

Add OK Apply Repeat these steps for a New Set Name T_flame of 4000 oF applied to Node 999, located to the right of the nozzle and for a New Set Name T_fuel of 200oF applied to Node 221, located at the lower left corner of the model at the fuel stream inlet. Create the ambient convection boundary condition. Use a New Set Name Amb_conv, a Convection Coefficient of 500.0, and a Fluid Node 998.

◆ Loads/BCs Create/Convection/Element Uniform Option


New Set Name

Amb_conv

Target Element Type

2D

Input Data...

12-20

Convection Coefficient

500

Fluid Node ID

Select Surface or Edges

Add


12-21



Can Be Obstructing Surface


◆Geometry

Select Menu

Add 12-22


WORKSHOP 12


OK Apply Create the radiation effect in the still air gap.

◆ Loads/BCs Create/Radiation/Element Uniform Option

Template, View Factor

New Set Name

Still_air_rad

Target Element Type

2D

Input Data... Enclosure ID

2

VFAC Template ID

10

Ambient Node ID

Can Be Obstructing Surface

There are only 2 entries in this Input Data form. VFAC Template ID and Enclosure ID. OK Select Application Region... Geometry Filter

◆Geometry


Apply 4.

Equivalence nodes.

Select the Finite Elements Applications radio button if not already selected. Set the Action, Object, and Method to Equivalence/All/Tolerance Cube. Select apply to complete the function.

Equivalen ce Nodes

Equivalence/All/Tolerance Cube Apply The nodes bounding the interior cracks will be circled in the display and the Command Line will indicate that a number of nodes are deleted.


13-7

Create micro-functions

The model should now appear as shown below.

5.


Define element properties for 1D Flow network bar elements using IOPT 2 for automatic friction factor calculation.

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/1D/Flow network bar. Enter Property Set Name Entry. Select the Input Properties... box. In the Input Properties chart, follow the steps below and enter the values that correspond to the property name. Select OK to close the form.Click in the Select Members box and select Curve 1 in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/1D/Flow network bar Property Set Name

Entry

Input Properties...

13-8

[TID]

1

IOPT

2

[Pipe diameter]

0.0625

[Pipe length]

50.00


WORKSHOP 13

A Sprinkler System Hydraulic Analysis

[Pipe roughness]

0.0

[Fluid density]

62.46

[Fluid viscosity]

6.764e-4

OK

Select Point

Add OK Apply Create a Variable, Mass Flow Rate named Full with Template Id 100 in the Input Data form. In the Select Application Region form pick Point 13, 14. Create/MassFlow Rate/Nodal Option:

Template

New Set Name

Full

Input Data... Mass Flow Rate Multiplier

1.0 MSC.Patran 312 Exercise Workbook - Release 2001

13-15


Template ID

100

OK Select Application Region... Select Points (hold down key)

Add OK Apply New Set Name

Quarter

Input Data... Mass Flow Rate Multiplier

1.0

Template ID

25

OK Select Application Region... Select Points (hold down key)

OK OK Apply


11. Read Result via the Analysis Form. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an npX.nrf.01 results file in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_13.db database. Applying the analysis created a new subdirectory with the same name as the Job Name; exercise_13/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.


/exercise_13


np0.nrf.01


pthermal_1_pnodal.res_tmpl

OK Apply Once he hydraulic results are read in, use Insight to post process the data. Insight provides a mechanism for increasing the diameter of the Bar 2 elements to view the results.

◆ Insight Create/Fringe Results Selection... Current Load Case(s) 13-20

2.1-Hydraulic Time: 0.0000


WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Update Results Fringe Result

1.1-Pressure,

OK Fringe Attributes... Edge Width

5

Style

Cylinder

OK Target:

All Edges

Apply The result should now appear as shown on the front page of the exercise. Use the vi editor in UNIX to open the qout.dat.01 file in the exercise_13 Job Name subdirectory and determine whether the design requirements are met: an entry volumetric flow rate not to exceed 12 GPM and a sprinkler head pressure above 30 psi.

12. Quit MSC.Patran Do not delete the database when you finish this exercise it will be used in a future exercise. In that exercise we will improve execution time and reduce viewfactor file size. To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.


Quit MSC.Patr

13-21

Quit MSC.Patran

13-22


WORKSHOP 14

Midterm: Build a Simple 2 Plate Model

Objective: ■

Build a simple two plate model which meets specified requirements.

■

Prepare the model for analysis and open a UNIX shell to observe the file creation and analysis process.

■

Run the analysis and use UNIX and utility commands to monitor the progress of the analysis.


14-1

14-2


WORKSHOP 14

Midterm Exam: Build a Simple 2 Plate

Model Requirements: The purpose of this exercise is to create a model with less guidance than has been provided in previous exercises. When the model is ready for analysis you will open a UNIX shell and observe the sequence of file creation paying special attention to files which provide feedback on the progress of the analysis. The model must meet the following requirements (see Figure on p 14-6) ■

2 - 1 x 1 x 0.001 meter plates with an MID of 353 (steel).

■

Plate surface normals shall face each other.

■

Each plate shall have a quadrant overlapping the other such that each plate has a corner point coincident with the center point of the other plate in Plan view.

■

The plates shall have a 0.05m gap between them.

■

Each plate shall have a mesh of 12x12 quad elements (global edge length 0.083).

■

Only one vertical edge of each plate shall have fixed boundary temperatures. The left most edge (x=0) shall be 0 degrees Celsius; the right most edge (x=1.5) shall be 150 degrees Celsius.

■

The two plates shall be thermally coupled by a single radiation boundary condition. Each plate has an emissivity of 0.1. Use a TID of 100 and an Enclosure ID of 1.

■

All boundary conditions and element properties shall be applied to geometry.


14-3

Open a new database



■

Create a model which meets the specified requirements.

■

Review your model against the checklist of questions.

■

Open a UNIX shell before submitting the model for analysis.

■

Submit the model for analysis and use the commands described to monitor its progress.

■

Debug, if necessary and resubmit after deleting all the files in the jobnamed subdirectory.

■

Read in results file and plot results.

■

Quit MSC.Patran.


1.


Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name exercise_14.db to the new database by clicking in the New Database Name box and entering exercise_14. Select OK to create the new database. File New... New Database Name

exercise_14

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form.

14-4

Tolerance

◆ Default

Analysis Code

MSC/THERMAL


WORKSHOP 14


OK 2.

Create a model which meets the specified requirements.

Based on what you’ve practiced, create the model according to the Model Requirements

Create a model

When completed model, should fit description shown on the next page. Note: The radiation boundary condition Input Data form has several list boxes for data entry. Despite the fact that all of the list boxes on the Input Data form appear to be required entries, you need only provide an Enclosure Id and a VFAC Template ID for this exercise. The other fields will be explored further in Exercise 21.


14-5

Create a model

14-6


WORKSHOP 14

3.

Midterm Exam: Build a Simple 2 Plate Review your model against the checklist of questions.

Did you use the various view icons to verify the placement of geometry? Did you check surface normals using Geometry/Show/Surface/Normal?

Review your model

Is the element type 2D/Shell with Material 353 and thickness 0.001? Was your Target Element Type: 2D for the radiation boundary condition? Did you plot LBC markers to verify 2 fixed temperatures and radiation? Does the radiation LBC use VFAC Template ID=100 and Enclosure ID=1? Have you created template .dat.apnd with *================ VFAC 100 0.1 *================ and no blank lines? In the Analysis form have you set: Requested Calculation and Output Temperature scales to degrees Celsius? Have you requested Perform Viewfactor in Solution Type form?

4.

Open a UNIX shell before submitting the model for analysis.

Once the model is verified, the template.dat.apnd file is built, and the Analysis form is complete, iconify the MSC.Patran viewport and open a new UNIX shell to get a UNIX prompt. Use the UNIX ls and cd commands to get to the directory in which your database resides. When you are located in the directory type at the prompt: $ cd exercise_14

5.

Open a UNIX shell

but do not hit or enter


Return to the open Analysis form and check Apply. After the stops scrolling and the Heartbeat is again green , change focus to the UNIX window and use the cd

Submit the model

Command Line History Window


14-7

Debug

exercise_14 command with a carriage return. Repeated execution of ls within the Job Name subdirectory will show you the progress of your analysis: Once the file vf.msg.01 appears, type: $ tail -f vf.msg.01 This will provide a continuous status of the viewfactor run. When viewfactor is complete it will end the status with a message, Successful Execution Completed. Use the c key combination to terminate the tail function. Repeatedly input a sequence of ls commands until a stat.bin file appears in the directory list. Once you the see the stat.bin file type: $ qstat c to monitor the progress of the network analysis. This command will self terminate after 20 repetitions or upon job completion. Monitor the data from the qstat command to determine the numerical status of the analysis. Check for the existence of an nr0.nrf.01 results file. If it exists the numerical analysis is complete and successful.

6.

Debug

Debug, if necessary, and resubmit after deleting all the files in the jobnamed subdirectory.

If Step 5 does not yield a results file then determine what went wrong. Is there a patqb.log file? If so, then is there a patq.msg file? If there is no patqb.log file then look in the MSC.Patran Command Line History Window or in the MSC.Patran interface for any error messages. If there is a patqb.log file and no patq.msg file then look for error messages in patqb.log. If there is a patq.msg file then look for error messages in it. If there are no error messages in the patq.msg file but this analysis requests that a viewfactor run be made then is there a vf.msg file? If there is a vf.msg file then look for error messages in it. For this analysis answering the above questions should provide a clue to the problem. 14-8



WORKSHOP 14

Once the error is found and resolved Repeat Steps 4 and 5. Remember that now many of the files will have an extension index which has been incremented by 1, e.g., vf.msg.01 to vf.msg.02. If it is convenient you may delete all the files from the exercise_14 Job Named subdirectory prior to resubmitting the analysis. 7.


From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.


Recall that p3 was initiated from a working directory which contained the microcircuit.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_14/. By using Read Result in the Analysis form and Select Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file.

◆ Analysis Read Results/Result Entiies Select Results File... Directories

/exercise_14


nr0.nrf.01





TIME: 0.0000000000D+00 S...


Temperature,


14-9

Quit MSC.Patran


Display:

Element Edges


Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise.

Quit MSC.Patr

14-10

8.

Quit MSC.Patran.



WORKSHOP 15

User Supplied Subroutines

Objective: ■

Create a user subroutine UHVAL that computes the values for the heat transfer coefficient.


15-1

15-2


WORKSHOP 15


Model Description: In this exercise the Convection Correlation will be supplied by the user. You will write the necessary code to evaluate the Convection Correlation in the user subroutine UHVAL. This Qtran subroutine will compute the values for the heat transfer coefficient and return those values to the main program. An iron slab is modeled in 2-dimensions. A heat flux of 1000w/m2 is imposed on the bottom edge of the slab. The top surface convects heat to the ambient temperature at 300K with a heat transfer coefficient defined by a user supplied subroutine. Tamb = 300 K

1m X 10m

Iron

Heat flux

1000W/m2


Start MSC.Patran and create a new database named, exercise_15.db.

■

Create the 2D model geometry.

■

Mesh the geometry with Quad4 elements and a Global Edge Length of 0.2.

■

Create an ambient node for convection boundary conditions.

■

Apply properties.

■

Create values for distance from the leading edge using Fields and Create/Spatial/PCL Function.

■

Define boundary conditions in Loads/BCs.

■

Copy ulib.f. MSC.Patran 312 Exercise Workbook - Release 2001

15-3

Open a new database ■

Modify and compile ulib.f.

■


■

Read the results file and plot temperature an heat transfer coefficient results.

■

Quit MSC.Patran.


1.


Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_15.db to the new database by clicking in the New Database Name box and entering exercise_15. Select OK to create the new database File New... New Database Name

exercise_15

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK

Create plate geometry

15-4

2.

Create the 2D model geometry.

To create the Surface that will represent the geometry of the 2D-model click on Geometry in the Main Window and set the Action, Object, and Method respectively to Create, Surface, and XYZ. Change the Vector Coordinates List to <10, 1, 0> and click on the Apply button to create the Surface.


WORKSHOP 15


◆ Geometry Create/Surface/XYZ Vector Coordinate List

<10 1 0>

Apply 3.

Mesh the surface with an IsoMesh of quad4 elements, global edge length of 0.2.

Select the Finite Elements Applications Radio Button and set the Action, Object, and Type respectively to Create, Mesh, and Surface. Enter, 0.2, for the Global Edge Length of the Quad4 elements you are now creating. Click in the Surface List box and then select Surface 1 in the viewport. Click on Apply to create the element.



0.2

Surface List

Apply


15-5

Create Ambient Node


4.

Create Ambient Node

Create an ambient node for convection.

To create the ‘Ambient’ Node, click on Finite Elements in the Main Window. Set the Action, Object, and Type respectively to Create, Node, and Edit. Change the Node Id List to 999, set the Associate with Geometry option to off, and then click in the Nodal Location List. Select the Screen Position select icon in the Select Menu (the right-most icon) and then locate the Node somewhere above the model’s center. Click on Apply to create Node 999.

◆ Finite Elements Create/Node/Edit Node Id List

999

Associate with Geometry (toggle off) Node Location List

and

Add Apply 6.

Create values for distance from the leading edge using Fields and Create/Spatial/PCL Function.

Spatial functions can be created in the Fields form using the Action/Object/ Method Create/Spatial/PCL Function.


◆ Fields Create/Spatial/ PCL Function Field Name

X_Dist

Scalar Function

’X+1.0

Apply


15-7


Fields Action:

Create Spatial

Object: Method:

PCL Function

Existing Fields

Field Name X_Dist Field Type Scalar

Vector

Coordinate System Type Real Parametric Coordinate System Coord 0 Scalar Function ('X, 'Y, 'Z) 'X+1.0


7.

Define boundary condition in Loads/BCs.

To assign a heat flux of 1000 W/m2 to the bottom of Surface 1, click on Loads/BCs in the Main Window. Set the Action, Object, and Type respectively to Create/Heating(P Thermal)/Element Uniform. Enter, Bott_Surf_Flux, for the New Set Name and then set the Target Element Type to 2D. Select Input Data and enter 1000 for Heat Flux. Click on OK to close the Input Data form. Next, click on the Select Application Region button and set the Geometry Filter to Geometry in the Select Application Region form. Click in the Select Surfaces or Edges box and then select the edge selection icon (second icon from left) in the Select Menu. Select the bottom edge of Surface 1 in the viewport. Click on the Add and OK buttons to close the form. Click on the Apply button to create the Heat Flux boundary condition.

◆ Loads/BCs Create/Heating/Element Uniform

15-8

Option:

Flux, Fixed

New Set Name

Bott_Surf_Flux


WORKSHOP 15

User Supplied Subroutines 2D

Target Element Type:

Input Data... 1000

Fixed Heat Flux

OK Select Application Region... Select Menu

Select Surfaces or Edges

Add OK Apply To apply the (yet to be defined) Convection Coefficient click on Loads/BCs in the Main Window and set the Action, Object, and Type respectively to Create/Convection/Element Uniform, option: Template, Convection. Enter, Conv_Coeff_Spatial, in the New Set Name box and then change the Target Element Type to 2D. Next, click on the Input Data button, deselect “Fixed”, and enter the field X_Dist for the Conv GP2/GP3, a Convection Template ID of 1, and 999 for the Fluid Node ID. Click on OK to close the Input Data form. Click on the Select Application Region button in the Load/Boundary Condition form. Using the Select Application Region form select the top edge of Surface 1. Click on the Add and OK buttons to close that form. Finally click on Apply to assign the boundary condition.



New Set Name

Conv_Coeff_Spatial


2D

Input Data... Fixed Select Spatial Field...

(deselect)

OK Select Application Region... Geometry Filter 15-10

◆ Geometry


WORKSHOP 15


OK OK Apply

11. Read results file and plot results.

Read Result

After completion of the analysis read and post-process the results. The resulting figure should look like the one in the title page of this exercise.

◆ Analysis Read Results/Result Entities Select Results File... Directories 15-14

/exercise_15


WORKSHOP 15



nr0.nrf.01


pthermal_nod_T.res_tmpl

OK Apply Warning OK To plot the results to posted FEM use the Results Application radio button.


TIME: 0.0000000000D+00 S...


Temperature,


Display:

Element Edges


Fixed

Significant figures

4

OK Apply


15-15

Quit MSC.Patran

Select the Select Result icon.


Average Convection Coefficient

Apply

Quit MSC.Patr

15-16

12. Quit MSC.Patran To stop MSC.Patran select File on the Top Menu Bar and select Quit from the drop-down menu.


WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Objective: ■

Demonstrate MSC.Thermal capabilities for gap convection problems.

■

Practice basic modeling skills using MSC.Patran.


16-1

16-2


WORKSHOP 16


Model Description: In this exercise you will create a simple 3D model representing the entry region of a concentric tube, counterflow heat exchanger. Owing to symmetry considerations only one-fourth of the heat exchanger configuration needs to be modeled. A team of university students is considering a makeshift heat exchanger, to cool and discard gaseous coolant from a small reactor. The heat exchanger is designed to “begin” at the reactor coolant plenum. In the event of an emergency, a safety valve would open to draw the coolant from the plenum into the exchanger (a process which will require approximately 60 seconds to complete). A secondary liquid coolant would then be used to decrease the temperature of the reactor coolant, before the reactor coolant enters a complex filtration process. The existing reactor coolant system is comprised of steel; and, the material proposed to contain the secondary coolant flow is simple lead. At the junction between the plenum and the heat exchanger, the gaseous fluid would exhibit a high mass flow rate at 350oC; the entry length variation of the convection coefficient between the steel and the gas is expected to follow: h = 200-13000*z3 w/m2K (where z is the distance from the plenum). The liquid coolant will flow between the steel coolant tube and its own lead housing, will be fully developed and is expected to exhibit a high convection coefficient (3000 w/m2K). The student’s prime concern with the design is the determination of the maximum temperature that the lead tube will exhibit after 60 sec of use. Lead Secondary Liquid Coolant Reactor Coolant Plenum 350oC

Steel Z h(z) Reactor Coolant


16-3

Open a new database


Create a new database named exercise_16.db.

■

Use the Create and Edit actions on the Geometry form to constuct a 2D representation of the heat exchanger.

■

Mesh the 2D geometry created in the previous step and use Sweep/Element/Extrude to develop he 3D FEM model.

■

Create 4 nodes to represent the spatial variation of the convection coefficient of the reactor coolant over the entry length.

■

Apply the appropriate Element Properties to the FEM model: Quad4’s - Steel MID 353; Hex8’s - Lead MID 21.

■

Create/Spatial/PCL Function to define the variation of the convection coefficient of the reactor coolant flow in the streamwise direction.

■

Apply a fixed temperature of 350oC to the nodes representing gasous coolant.

■

Create 2 Fixed Coefficient Convection Boundary Condtions.

■

Perform a Transient Analysis for 60s assuming a global initial temp of 25oC.

■


■

Read results file and plot results.

■

Quit MSC.Patran.


1.


Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_16.db to the new database by clicking in the New Database Name box and entering exercise_16.

16-4



WORKSHOP 16

Select OK to create the new database. File New... exercise_16

New Database Name

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Approximate Maximum Model Dimension to 0.07, and the Analysis Code to MSC/ THERMAL. Select OK to close the New Model Preferences form. Approximate Maximum Model Dimension

0.07

Analysis Code

MSC/THERMAL

OK 2.

Use the Create and Edit actions on the Geometry form to constuct a 2D representation of the heat exchanger.

Select the Geometry Applications Radio Button. Create a surface using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below.

Create 2D heat exchanger

◆ Geometry Create/Curve/2D ArcAngles Radius

0.05

Starting Angle

180

End Angle

270

Apply Radius

0.06

Apply Create/Surface/XYZ Vector Coordinates List

<-0.07 -0.07 0>

Apply


16-5

Create 2D heat exchanger

Turn on the label by using the Tool Bar Show Labels icon.

Edit/Surface/Break Option:

Curve

Surface List:

Surface 1

Break Curve List

Curve 2

Apply Message! (delete original surface)

Yes

Delete/Any Geometric Entity List

Surface 3

Apply At any time during this exercise, use the Tool Bar Refresh graphics icon to refresh the graphics when necessary.


16-6



WORKSHOP 16

3.

Mesh the surface with quad4 elements. Use the Paver and a global edge length of 0.006.

Select the Finite Elements Applications Radio Button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.006 and select Surface 2for inclusion in the Surface List.

Mesh the surfaces


0.006

Mesher

◆ Paver

Surface List

Surface 2

Apply Create/Mesh/Curve Global Edge Length

0.006

Curve List

Curve 1

Apply Sweep/Element/Extrude Mesh Control ... Number =

20

OK Extrude Distance

0.2

◆ Delete Original Elements Base Entity List

Apply Use the Tool Bar Hide Labels icon and Iso 1 View to get a clearer view of the graphics. Also, increase the size of the nodes by using the Tool Bar Node Size icon so the four boundary nodes will be more visible.

Hide Labels

Iso 1 View

Node Size

Fit View


16-7

Create ambient nodes


4.

Create ambient nodes

Create 4 nodes to effect a spatial variation of the convection coefficient magnitude to represent a developing flow.

Using the Finite Elements form, create 4 boundary nodes which are not associated with geometry. The nodes are numbered 9996 to 9999. Click in the appropriate list boxes to edit the default values and change them to values listed below. Create/Node/Edit Node ID List

9996


[0 0 0]

Apply Node ID List

9997

Node Location List

[0 0 0.05]

Apply 16-8


WORKSHOP 16


Node ID List

9998

Node Location List

[0 0 0.12]

Apply Node ID List

9999

Node Location List

[0 0 0.20]

Apply Rotate the display to verify the locations of the new nodes. Using the Iso 2 View, the model should appear as shown below.

Revert the display back to the Front View for the next section.


16-9


5.


Apply two element properties to the elements using the material property MID’s 353 and 21.

In a typical modelling sequence the Materials Application radio button would be the next stop to define a material for application in Element Properties. However, MSC.Thermal includes a Material Properties Database which contains 971 materials with thermal properties already defined. We will use this database to facilitate the analysis. Select the Properties Applications radio button. Set the Action, Dimension, and Method to Create/2D/Shell. Enter Property Set Name Steel. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and enter 353, and thickness of 0.005m. Select OK to close the form. First, select 2D element from the Select Menu Form. Click in the Select Members box and drag a rectangle around the model in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Shell Property Set Name

Steel


353

Shell Corner Thickness

0.005

OK Select Members/Select Menu

<2D Element icon, second from top>

Select Members

Add Apply

6.

Create/Spatial/PCL Function to define the variation of the convection coefficient of the reactor coolant flow in the stream direction.

Create Function

◆ Fields Create/Spatial/PCL Function Field Name

convection_f_of_z

Scalar Function (‘X, ‘Y, ‘Z)

200-(13000*’Z*’Z*’Z)

Apply Show Select Field To Show

convection_f_of_z

Specify Range... Maximum

0.2

No. of Points

10

OK Apply


16-11


The XY Result Window and Table should appear as shown below.

Close the window and table by clicking on the Unpost Current XYWindow. Cancel Unpost Current XYWindow 7.

Apply a fixed temperature of 350oC to the nodes representing gasous coolant.

Begin applying boundary conditions. Select the Loads/BCs Applications Radio Button. Create a fixed 350oC nodal boundary temperature named interior_flow. In the Input Data form define the fixed temperature. In the Select Applications Region form pick Node 9996 to 9999 located in the upper right corner of the display screen.


Fixed

New Set Name

interior_flow


350.0

OK 16-12



WORKSHOP 16


Select Application Region... Geometry Filter

◆ FEM

Select Nodes

Close OK Select Application Region... Geometry Filter

◆ FEM

Select 2D Elements or Edges

Add OK Apply MSC.Patran 312 Exercise Workbook - Release 2001

16-13


A green line should verify the newly defined association. Before creating the next convection condition, make sure that the polygon picking preference is set at Enclose entire entity. Preferences Picking... Rectangle/Polygon Picking

◆Enclose entire entity

Close Now, construct the next Between Regions Convection condition called outer_flow as follow. Create/Convection/Element Uniform Option:

Fixed Coefficient

New Set Name

outer_flow


3D

Region 2:

2D


3000


◆ FEM

Coupling Method

Closest Approach

Select 3D Element Faces

key and the left mouse button to create a polygon selecting only those lead element which contact the outer fluid flow>

Add Select 2D Elements or Edges

Apply

Select Viewing/Scale Factors... to increase the scale of the model in the Ydirection. This will expand the model display to facilitate viewing, picking, and displaying results. Only the model display is scaled not the actual model dimensions. Scaling may throw the coordinate system symbol out of the display viewport. Viewing Scale Factors... Model Y

5.0

Apply Cancel

17-6


Analysis of a Fuel Nozzle Tip Using Convection Between Regions

WORKSHOP 17


2

3 1

5 2

1

4

6

To create the surfaces that will represent the geometry where the Steel and Still Air will reside set the Geometry form Action, Object, and Method to Transform/Surface/Translate. Click in the Translator Vector databox and then choose the following Tip and base points icon.

Click on Point 5 and Point 6 to define the translation vector. Next, set the Repeat Count to 2, click in the Surface List databox and drag a rectangle around Surface 1 and Surface 2 in the viewport.


Repeat Count

2

Auto Execute Surface List

Apply MSC.Patran 312 Exercise Workbook - Release 2001

17-7

Create the nozzle and fluid stream geometry


2 1 7

3 1 3 5

10

4 8 11

5 2 4 6

6 9 12

The flow of fuel within the nozzle will be modelled with advection bars. Create the two curves where the bars will be placed. Change the Action, Object, and Method to Create/Curve/XYZ. For the first curve set the Vector and Origin Coordinates List to, <4.5 0 0> and [0 0 0] respectively.

◆ Geometry Create/Curve/XYZ Vector Coordinates List Auto Execute Origin Coordinates List

<4.5 0 0> [0 0 0]

Apply To create the second curve set the Vector and Origin Coordinates List to <0.5, 0, 0> and Point 14 respectively. Vector Coordinates List

<0.5 0 0>

Origin Coordinates List

Apply

17-12



WORKSHOP 17


5.

Use Finite Elements/Create/Node/Edit to create two ambient nodes 998 and 999 for the ambient and flame temperatures.

In the Finite Elements form create a boundary node which is not associated with geometry. The node is numbered 998. Locate the node at [2.5 0.3 0].

◆ Finite Elements Create/Node/Edit 998

Node ID List Associate with Geometry

Auto Execute

[2.5 0.3 0]

Node Location List

Apply Repeat for Node 999 located at [5.2 0.15 0]. Increase the display size of nodes. Use either Display/Finite Elements ... or the associated Tool Bar icon to change the node size. Display Finite Elements... Node Size

9

Apply Cancel or,

Select Display/Entity Color/Label/Render.../Hide All Entity Labels or use the Tool Bar Labels Hide icon to remove all labels and unclutter the display. Display Entity Color/Label/Render... Hide All Entity Labels Apply MSC.Patran 312 Exercise Workbook - Release 2001

17-13

Equivalence nodes

Cancel or,


Equivalen ce nodes

6.


Using the Finite Elements form set the Action/Object/Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.


Apply element properties to nozzle

17-14

Apply Thermal Axisymmetric element properties to the nozzle and Advection Bar element properties to the flow stream.

Use Tool Bar Label Control icon to turn on Surface labels. Close


WORKSHOP 17


Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal Axisymmetric. Enter Property Set Name Nickel. Select the Input Properties... box. Click in the Material Name box and enter 243. Select OK to close the form.Click in the Select Members box and select Surfaces 1, 2, and 4 in the viewport using the shift-left mouse button. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal Axisymmetric Property Set Name

Nickel


243

OK Select Members

Select Members

Add Apply Though the Specific Heat MPID appears in square brackets it is, in fact, not an optional entry. Even in a steady state analysis advective conductors are derived from the product of specific heat and mass flow rate. 8.


Define three fixed temperature, three convective, and two radiative boundary condition in Loads/BC’s.

Select the Loads/BCs Applications radio button. Create a fixed 1000oF nodal boundary temperature named T_air. In the Input Data form define the fixed temperature. In the Select Region form pick Node 998, located above the nozzle model.


Fixed

New Set Name

T_air


1000.0


◆ FEM

Select Nodes


◆Geometry

Select Menu

Select an Edge icon


Add Click in Coupling Region Select Surface or Edges


Add Click in Coupling Region

Can be obstructing surface


◆Geometry


17-19


Select Menu

Select an Edge icon




WORKSHOP 17

Add OK Apply With boundary conditions applied the model should now appear as shown below.

9.

Create and post a group name Nozzle which only includes the nozzle elements. You will create a group which will contain only entities associated with the nozzle.

Create a group maned nozzle

Group Create... New Group Name

Nozzle

Make Current


17-21

In unix create template.dat.apnd file

Entity Selections

Apply Cancel The model should now appear as shown below.

Reduce the node size with the Node Size icon.

In unix create template.d at.apnd file

10. Use the new Analysis/Build Template form to create a file named template.dat.apnd containing the VFAC definitions. Using Analysis/Build Template, create and edit the file template.dat.apnd in the directory which contains your database and where MSC.Patran is running. Create a definition VFAC for the flame radiation boundary condition. Shown below is the final form of the template.dat.apnd file created for this exercise. Note that any comment lines must be started with an * in column 1

17-22


WORKSHOP 17


and make sure that there are no blank lines especially at the end of the file. Start typing from the first column and do no enter any blank lines.

◆ Analysis Build Template Create Template File... Create/VFAC/Data Entry VFAC ID

10

Emissivity

0.8

Apply Write File... OK Cancel Cancel VFAC 10 0 0.8 1 A mat.dat.apnd file is required to define the specific heat property of the advecture flow. The mat.dat.apnd file required for this exercise is identical to that created in Exercise 12. The final form of the mat.dat.apnd file is shown below for reference. MPID 1 C F 1.0 MDATA O.57 / 11. Prepare and submit the model for analysis specifying that it is steady state analysis including viewfactor and radiation resistor computations, for an axisymmetric model with unit conversions from inches to feet that all calculations and output should be in oF.



17-23


Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

◆ Analysis Analyze/Full Model/Full Run Translation Parameters... Model Dimensionality

◆ Axisymmetric Geometry, R Z Co-ordinates

Radial, R Co-ordinate

◆ Yaxis ◆ Xaxis

Centerline, Z Co-ordinate

Perform Geometry Units Conversion From Units

inches

To Units

feet

File to Extract Undefined Materials:

3,mpidfph.bin (BTU-feet-lbmhour)

OK Solution Type... Perform Viewfactor Analysis


◆ Fahrenheit

Run Control Parameters... Stefan-Boltzmann Constant

1.7140E-9 BTU/HR/FT2/R4

Initial Temperature =

1000.0

Initial Temperature Scale

◆ Fahrenheit

OK OK Output Requests... Units Scale for Output Temperatures

◆ Fahrenheit

Units Definition for Time Label

Hours

OK 17-24


WORKSHOP 17


Submit Options... Make sure both Create ViewFactor Control FIle (vf.ctl) and Execute Viewfactor Analysis are selected. OK Apply

12. Read and plot the results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.


P3 was initiated from a working directory which contained the exercise_17.db database. Applying the analysis created a new subdirectory with the same name as the Job Name, exercise_17/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.


/exercise_17


nr0.nrf.01



OK Apply After results are read in plot the results. To plot the results use the Results Application radio button. Select you results file.

◆ Results MSC.Patran 312 Exercise Workbook - Release 2001

17-25

Quit MSC. Patran

Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...


Temperature,


Display:

Element Edges


Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise. 13. Quit MSC.Patran

Quit MSC. Patran


17-26


WORKSHOP 18

Post-processing the Hybrid Microcircuit Results with Insight

Objective: ■

In this exercise you post-process the results of the hybrid microcircuit analysis using Insight tools.


18-1

18-2


WORKSHOP 18

Post-processing the Hybrid Microcircuit

Model Description: In this exercise you will reopen the hybrid microcircuit database which now includes results data. You will use the Insight post-processing tools to enhance the presentation of the available results. Two isothermal surfaces will be generated which will provide a three dimensional view of the temperature field within the model. Also a series of planes will be created to expose the interior pattern of temperatures.



■

Use Viewing/Named View Options... and Viewing/ Transformations... to change to an X-Z view.

■

With Display/Entity Color/Label/Render... change render style to hidden line and use Transformations... to readjust display to a better point of view for results.

■

Use Insight to create an Isosurface Tool with which to view isothermal surfaces contained within the model.

■

Use Insight to create a second Isosurface which will define 5 display planes through the model on which fringe results will be displayed.

■

Quit. MSC.Patran.


18-3





Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and open the existing microcircuit database. File Open... Database List

microcircuit.db

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format.

Change to an X-Z view

2.

Change the view to an X-Z view. (This step can also be accomplished simply by selecting the Tool Bar Bottom view icon).

Select Viewing from the Menu Bar to change to a default_view of the model hybrid_fem entities. Preferences Graphics... Auto Fit View

Apply Cancel Viewing Named View Options... Select Named View

default_view

Close

18-4


WORKSHOP 18

Post-processing the Hybrid Microcircuit

Select Viewing from the Menu Bar and use Transformations... to adjust the display to an X-Z view. When the rotation increment is defined use the -X rotation icon to complete the X-Z view. Viewing Transformations... Options... Rotation increment (deg)

90

◆ Screen Relative OK

Select Fringe Result:

Temperature,


19-9

Quit MSC.Patran


Display:

Element Edges


Fixed

Significant figures

4

OK Spectrum... Current Selection:

hot cold 16

Apply Cancel Apply

(to create Fringe)

Create/Animation Plots to Animate:

None_FRI_default_Fringe

Animations Method:

Global Variable

Select Global Variable:

Time

Number of Frames:

25

Apply

7.

Quit MSC.Patr

Stop Animate. Quit MSC.Patran.

Stop Animation To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

19-10


WORKSHOP 20

SINDA Translation of a PWB Model

Objective: ■

Create a model by playing a session file.

■

Produce a run-ready SINDA/G deck from the model and post-process the SINDA/G temperature results.


20-1

20-2


WORKSHOP 20


Model Description: In this exercise you will read a session file which will construct a board level PWB (Printed Wiring Board) heat transfer model. When the session file ends it will have produced a model that is ready to analyze. You will run the analysis in MSC.Thermal but you will also produce a run-ready SINDA/G deck. Since the platform on which you work this exercise may not have a SINDA/ G executable module, results from SINDA/G are provided. With the possible exception of actually running the SINDA/G analysis, you will have used MSC.Patran to produce a syntactically correct SINDA/G deck and read in the resulting temperatures.

0.25 x 0.25 in h = 6.72 w/sq.in-C 4 typ bottom of PWB 0.5 in

2 in. 1 in

0.25 x 0.50 in. h = 3.36 w/sq. in-C 4 typ bottom of PWB

3 watts

2 in

6 in.

0.5 in .1 w

2 in

1 in.

.1 w

.1 w

0.25 in

Y 0.5 watts

.25 w 2 in

.25 w

.25 w

X 8 in. PWB is 0.125 in. thick kx = ky = 0.825 w/in-C kz = 0.04 w/in-C Tambient = 70 C

NOT TO SCALE

Figure 1


20-3

Open a new database


Create a new database named exercise_20.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Use File/Session/Play... to read exercise_20.ses file and create the analysis model of Figure 1.

■

Prepare and submit model for analysis selecting Submit Option/Create SINDA File (model.sin).

■

Modify the Select Results File... filter to retrieve nr0.sin.

■

Modify the Select Rslt Template File... filter to use the sinda.res_tmpl template.

■

Plot SINDA/G results.

■

Go to the Job Name subdirectory to review the contents of model.sin.01.

■

Quit MSC.Patran.


1.


Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_20.db to the new database by clicking in the New Database Name box and entering exercise_20. Select OK to create the new database File New... New Database Name

exercise_20

OK

20-4



WORKSHOP 20

MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK

2.

Use File/Session/Play... to read exercise_20.ses file and create the analysis model of Figure 1.

Read Session FIle

In order to guarantee that the model you crated will have the correct node ID’s in the proper sequence, you will create the model from a session file. Node sequence and location is important since the nr0.sin file identifies model temperatures with node IDs. The session file, once initiated, will run autonomously until the model is completed. File Sessions Play...

Play from File

OK

5.

Modify the Select Rslt Template File... filter to use the sinda.res_tmpl template.

Select Rslt Template FIle... Filter

Modify Template FIle

Filter FIles

Add OK Apply

4.

Change the Job Name in the Analysis form to exercise_21.

On the Analysis Form change the Job Name to exercise_21. This will create a new subdirectory of files for this analysis which will facilitate comparing data between the two runs, exercise_14 and exercise_21.

Change Job Name

◆ Analysis Job Name

exercise_21


21-5

Modify template

5.

Modify template

Modify the template.dat.apnd file to include a collapse flag.

Use Analysis/Build Template to create a new template.dat.apnd file which includes a collapse flag entry. *============================ VFAC 100 0.1 1.0 0 0 0.0 0.0 0 100 VFAC 200 0.1 1.0 0 0 0.0 0.0 0 200 *============================ The main advantage of using COLLAPSE to collapse radiosity nodes is that this will result in a much smaller number of radiation resistors in the model. A smaller number of resistors usually means that the thermal analysis will proceed faster. In the best cases, the number of radiation resistors may be reduced by about a factor of four for 2D Cartesian or axisymmetric models and by about a factor of 16 for 3D models.

6.

Submit the model


Return to the open Analysis Form and check Apply. After the stops scrolling, change focus to the UNIX window and affect the cd exercise_21 command with a carriage return. Repeated execution of ls within the jobname subdirectory will show you the progress of your analysis: Once the file vf.msg.01 appears, type:

Command Line History Window

$ tail -f vf.msg.01 This will provide a continuous status of the viewfactor run. When viewfactor is complete it will end the status with a message, Successful Execution Completed. Use the c key combination to terminate the tail function. Again input a sequence of ls commands until a stat.bin file appears in the directory list. Once you the see the stat.bin file type: $ qstat c

21-6


WORKSHOP 21

Opt. Perf. of Radiation Interchange Analysis

to monitor the progress of the network analysis. This command will self terminate after 20 repetitions or upon job completion. Monitor the data from the qstat command to determine the numerical status of the analysis. Check for the existence of an nr0.nrf.01 results file. If it exists the numerical analysis is complete and successful.

7.

Debug

Debug, if necessary, and resubmit after deleting all the files in the jobnamed subdirectory.

If Step 5 does not yield a results file then determine what went wrong. Is there a patqb.log file? If so, then is there a patq.msg file? If there is no patqb.log file then look in the MSC.Patran Command Line History Window or in the MSC.Patran interface for any error messages. If there is a patqb.log file and no patq.msg file then look for error messages in patqb.log. If there is a patq.msg file then look for error messages in it. If there are no error messages in the patq.msg file but this analysis requests that a viewfactor run be made then is there a vf.msg file? If there is a vf.msg file then look for error messages in it. For this analysis answering the above questions should provide a clue to the problem. Once the error is found and resolved Repeat Steps 4 and 5. Remember that now many of the files will have an extension index which has been incremented by 1, e.g., vf.msg.01 to vf.msg.02. If it is convenient you may delete all the files from the exercise_21 Job Named subdirectory prior to resubmitting the analysis.


21-7



8.


From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. Recall that p3 was initiated from a working directory which contained the microcircuit.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_21/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file.


/exercise_21


nr0.nrf.01





Apply

22-6


WORKSHOP 22

If there are any surface that is pointing the -Z direction, change them with the following steps. Edit/Surface/Reverse Surface List

Select Geometry Entities


22-11

Apply View Factor boundary conditions

Select Surfaces or Edges

Add OK Apply Encl_201

New Set Name

Input Data... Enclosure ID

2

Vfac Template ID

200

Participating Media Node ID

OK 200

VFAC ID

Advanced Options... No. Wavebands

2

Ec

.9

The remaining information to be entered for the TID 200 row is shown in the table below. Each term of the command is defined in the P⁄THERMAL Users Manual. Shown below is a Table that lists the required information for the two VFAC commands to be created. TID

NBANDS

ε

τ

εid

τid

λ1

λ2

K flag

Collapse

200

2

0.9

0.4

0

0

0.0

5.0

0

0

0.2

0.4

0

0

5.0

1E6

0

0

OK


22-13

Apply View Factor boundary conditions

Apply

The contents of the resulting template.dat.apnd file are shown below for your reference.

VFAC 100 0 0.9 1. 0 0 0. 0. 0 0 VFAC 200 2 0.9 0.4 0 0 0.0 5.0 0 0 0.2 0.4 0 0 5.0 1.0E6 0 0 Write File... OK

22-14

Cancel

Cancel


WORKSHOP 22

Your model with its applied boundary conditions should now look like the one shown below.

Define Element Propertie

8.

Define the Element Properties for the models Iron material.

To do this click on the Element Props toggle in the Main Window. When the form appears set its Action, Dimension, and Type option menus respectively to Create, 2D, and Thermal 2D. Enter Iron, for the New Set Name and then click on the Input Properties… button. Enter 18 in the Material Name databox and then click on the OK button to close the form. Next, click in the Select Members box and select all the models surfaces in the viewport. Finally click on the Apply button in the Element Properties form.


Iron


22-15



18

OK Select Members

Introduction to Thermal Analysis Using MSC.thermal

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