Name:
Section: BSCE-4A
Subject: CE 424
Date:
ASSIGNMENT NO. 1 IN CE 424 DAMS, FUNDAMENTAL OF FLUID FLOWS, FLUID F LOW MEASUREMENT
I. IDENTIFICATION. Write your answer after each item number. Follow the format given to you. 1. A principle in flow measurement which state that, neglecting head loss the increase in kinetic ene rgy per unit weight is equal to the decrease in potential energy per unit weight. _________________________ _________________________ 2. It is a graphical representation of the total energy of flow. ______________________ _________________________ ___ 3. The hydraulic and energy gradients for a straight pipe and uniform diameter are parallel with each o ther because of ___________________ _________________________ ______ 4. It is the t he distance between the water surface of two reservoirs. ________________________ _________________________ _ 5. It is the distance between the EGL and the t he HGL. _______________________ _________________________ __ 6. The Venturi meter is used to measure the presence of flow in pipe system, the section of the pipe w ith the smallest pressure is the ___________________ _________________________ ______ 7. The head loss in a nozzle is e xpressed in terms o f ____________________ _________________________ _____ 8. A hydrostatic law of liquid which states that the theoretical velocity of a jet of liquid issuing out of orifice under a head h is equal to that acquired by the free-falling body dropping through a height h is known as ___________________ _________________________ ______ 9. It is an overflow structure built across an open channel for the purpose of measuring and c ontrolling the flow ___________________ _________________________ ______ 10. A mechanical device which when installed in the pipe flow system will add energy to the system. ___________________ _________________________ ______ 11. A series of siphon pipes of uniform diameter are to draw water to irrigate the farm. The pressure head at the summit of the siphon (considering the datum line of discharge e nd & neglecting HL) is equal to ____________________ _________________________ _____ 12. In fluid flow, if the fluid travels parallel to the adjacent layers and the paths of individual particles do not cross, the flow is said to be, ______________________ _________________________ ___ 13. In pipe flow, the horsepower of t he pump can be computed as the function of _______________________ _________________________ __ 14. The vena contracta of a sharp edged hydraulic orifice usually occur __________________ _________________________ _______ 15. In a Pitot tube, the point at the face of the tube facing the stream is called ________________________ _________________________ _ 16. The machine installed in the pipe that is used to convert the energy of flow into mechanical work is ___________________ _________________________ ______ 17. Type of weir where the discharge is expressed as Q=8/15/2g C tan /2 H^5/2 is _________________________ _________________________ 18. It is the increased pressure developed on impact with the Pitot tube as a result of localized kinetic energy reduction to zero ___________________ _________________________ ______ 19. The type of weir for which t he discharge varies linearly with the head. _________________________ _________________________ 20. It consists of a thin tube projecting into a tank having a length of about one diameter. ___________________ _________________________ ______
II. PROBLEM SOLVING. Write your solution after each item number. Follow the format given to you. 1. What is the theoretical velocity of flow in m/s through an orifice located 3.2 m below the water surface?
2. A tank filled with water to a depth of 2.4 m is accelerated upward at a rate of 3 m/s. the velocity of the discharge at the orifice 2cm in dia. located at the bottom of the tank is:
3. Neglecting air resistance, determine to what height a vertical jet of water could rise if projected with a velocity of 20 m/s.
4. An orifice located at the vertical side of a large tank is 8 m from the level ground. How long will it take for the water to reach the ground after opening the orifice?
5. A circular orifice is located 5 m below the water surface. If the tank is large & the dia. of the orifice is 5 mm, calculate the discharge in cu. m/s. C=0.60
6. Find the theoretical velocity generated by a 5-m hydraulic head.
7. The ave. velocity in a pipe flowing full of incompressible liquid is 3 m/s. after passing through a conical section that reduces stream’s cross-sectional area to 1/_ of its previous value, the velocity in m/s after the conical section is:
8. What is the rate of flow of water in cu. m/s passing through a pipe with a dia. of 20 mm and speed of 0.5 m/s?
9. A closed conduit with a 25 cm dia. pipe is connected to a 20 cm dia. pipe. If the velocity at the second pipe is 4 m/s, what is the velocity of the first pipe?
10. A nozzle inclined at an angle of 60 with the horizontal issues a 50 mm dia. w ater jet at a rate of 10 m/s. neglecting air resistance, what is the area of the jet at the highest point of the projectile?
11. The static head corresponding to flow of velocity of 3 m/s is:
12. A closed conduit with 20 cm dia. pipe is connected to a 15 cm dia. pipe. If the pressure head at the first pipe is 20 m, what is the pressure at pipe 2 carrying water at a rate of 0.5 cu. m/s?
13. A town requires 1.5 cu. m/s of water for its water supply. Determine the diameter of the pipe if the velocity is 2.5 m/s.
14. A water tank with a diameter 3 m is filled with water. If the water level is 2.3 m above a nozzle, what is the velocity of the water in m/s coming out of the nozzle? Neglect losses.
15. A large square tank has a 200 mm dia. nozzle 5 m below the water level. What is the pressure at a point 3 m below the water level?
Situational Problem 1 – A calibration test of a 15 mm dia. circular sharp-edged orifice in a vertical side of a large
tank showed a discharge of 1000 N of water in 81 secs at a constant head of 5 m. measurement of the jet showed that it traveled 4 m horizontally while dropping 1 m, determine: 16. The coefficient of discharge 17. The coefficient of velocity 18. The coefficient of contraction
III. MATCHING TYPE. Match Column A with Column B
COLUMN A _____1. It is the amount of fluid passing through a section per unit of time. _____2. This occurs when the amount of fluid passing a given cross section is constant with time. _____3. Through the research of this man, it is possible to predict approximately the characteristics of flow of any other fluid based on experiments on a particular fluid. _____4. This occurs when the path of individual fluid particles is irregular and continuously cross each other. _____5. The energy possessed by the fluid by virtue of its position with respect to a datum plane. _____6. It is a converging tube attached to the end of a pipe or hose which serves to increase the velocity of the issuing jet. _____7. It is a bent L-shaped tube with both ends open, used for measuring the velocity of liquids. _____8. Neglecting head loss, the increase in kinetic energy is equal to the decrease in potential energy. _____9. The ability of fluid mass to do work by virtue of its velocity. _____10. The American engineer who invented the Venturi meter. _____11. Neglecting friction, the total head, or the total amount of energy per unit weight, is the same at every point in the path of flow. _____12. Converging path lines result in ___________________________ in each path line. _____13. It is the rate at which work is done. _____14. It extracts flow energy to do mechanical work which in turn converted into electrical energy. _____. It is the graphical representation of the total potential energy of flow.
COMUMN B A. B. C. D. E. F. G. H. I. J. K. L. M. N.
Pitot tube Bernoulli’s Energy Theorem Increased velocity Flow rate Osborne Reynolds Clemens Herschel Steady flow Uniform flow Venturi principle Turbine Turbulent flow Elevation energy Hydraulic Grade Line Energy Grade Line
O. Nozzle P. Power Q. Kinetic Energy R. Orifice S. Laminar Flow
IV. DAM
A dam is triangular in cross-section with the upstream face vertical. Water is 8 m high. The dam is 10 m high and 8 m wide at the base and weighs 23.5 kN/m3. The coefficient of friction between the base and the foundation is 0.75. consider hydrostatic uplift to vary uniformly from full hydrostatic pressure at the hee l to zero at toe. Draw the figure of the dam with the location of Rx, Ry, x
Determine: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Rx Ry RM OM F.S.s F.S.o X E Maximum unit pressure on the foundation Minimum unit pressure on the foundation Draw the base of the dam with the location of e, maximum unit pressure on the foundation, minimum unit pressure on the foundation
