Name of the College : Valliammai Engineering College
Subject : Fluid Mechanics and Machinery
Website : valliammai.co.in
Document Type : Question Bank
Department : Mechanical Engineering
Semester : III
Degree : B.E
Question Bank : https://www.pdfquestion.in/uploads/valliammai.co.in/1753-Fluid%20Mechanics%20and%20Machinery.pdf
Fluid Mechanics and Machinery Question Paper
DEPT. Of Mechanical Engineering
FLUID MECHAINCS AND MACHINERY
IIIrd SEMESTER
UNIT-I
INTRODUCTION
PART-A
1. A soap bubble is formed when the inside pressure is 5 N/m2 above the atmospheric pressure. If surface tension in the soap bubble is 0.0125 N/m, find the diameter of the bubble formed.
2. The converging pipe with inlet and outlet diameters of 200 mm and 150 mm carries the oil whose specific gravity is 0.8. The velocity of oil at the entry is 2.5 m/s, find the velocity at the exit of the pipe and oil flow rate in kg/sec.
Related : Valliammai Engineering College EE6351 Electrical Drives and Control B.E Question Bank : www.pdfquestion.in/1760.html
3. What is the variation of viscosity with temperature for fluids?
4. Find the height of a mountain where the atmospheric pressure is 730 mm of Hg at Normal conditions.
5. What is meant by vapour pressure of a fluid?
6. Distinguish between atmospheric pressure and gauge pressure.
7. What are Non-Newtonian fluids? Give examples.
8. Mention the uses of a manometer.
9. What do you mean by absolute pressure and gauge pressure?
10. Define the term Kinematic Viscosity and give its dimension.
11. What is meant by continuum?
12. State Pascal’s hydrostatic law.
13. What is specific gravity? How is it related to density?
14. How does the dynamic viscosity of liquids and gases vary with temperature?
15. How does the dynamic viscosity of (a) liquids and (b) gases vary with temperature?
16. What is the difference between gauge pressure and absolute pressure?
17. Differentiate between solids and liquids.
18. Define the following terms: (a)Total pressure (b)Centre (or) position of pressure.
19. What is meant by capillarity? 20. Define buoyancy.
21. What is viscosity? What is the cause of it in liquids and in gases?
22. State Pascal’s law.
PART-B :
1. A drainage pipe is tapered in a section running with full of water. The pipe diameters at the inlet and exit are 1000 mm and 500 mm respectively. The water surface is 2 m above the centre of the inlet and exit is 3 m above the free surface of the water. The pressure at the exit is 250 mm of Hg vacuum. The friction loss between the inlet and exit of the pipe is 1/10 of the velocity head at the exit. Determine the discharge through the pipe.
2. A pipe of 300 mm diameter inclined at 30° to the horizontal is carrying gasoline (specific gravity =0.82). A Venturimeter is fitted in the pipe to find out the flow rate whose throat diameter is 150 mm. The throat is 1.2 m from the entrance along its length. The pressure gauges fitted to the Venturimeter read 140 kN/m2 and 80 kN/m2 respectively. Find out the coefficient of discharge of Venturimeter if the flow is 0.20 m3/s.
3. Explain the properties of a hydraulic fluid.
4. A 0.5 m shaft rotates in a sleeve under lubrication with viscosity 5 poise at 200 rpm. Calculate the power lost for a length of 100 mm if the thickness of the oil is 1 mm.
5. (i) Derive Bernoulli’s theorem and state its limitations. (ii) A horizontal Venturimeter with inlet diameter 200 mm and throat diameter 100 mm is employed to measure the flow of water. The reading of the differential manometer connected to the inlet is 180 mm of mercury. If Cd = 0.98, determine the rate of flow.
6. Derive continuity equation from basic principles.
7. Derive Euler’s equation of motion for flow along a stream line. What are the assumptions involved.
8. A horizontal pipe carrying water is gradually tapering. At one section the diameter is 150 mm and flow velocity is 1.5 m/s. If the drop in pressure is 1.104 bar at a reduced section, determine the diameter of that section. If the drop is 5 kN/m2, what will be the diameter — Neglect losses?
9. State Bernoulli theorem for steady flow of an incompressible fluid. Derive an expression for Bernoulli equation and state the assumptions made.
10. (i)A 15 cm diameter vertical pipe is connected to 10 cm diameter Vertical pipe with a reducing socket. The pipe carries a flow of 100 1/s. At point 1 in 15 cm pipe gauge pressure is 250 kPa. At point 2 in the 10 cm pipe located 1.0 m below point 1 the gauge pressure is 175 kPa.
(1) Find whether the flow is upwards / downwards.
(2) Head loss between the two points
(ii) Differentiate Venturimeter andOrificemeter.
UNIT-II
FLOW THROUGH CIRCULAR CONDUITS
PART A
1. What is the physical significance of Reynold’s number?
2. Define boundary layer and give its significance.
3. List the causes of minor energy losses in flow through pipes.
4. What is T.E.L.?
5. What is Hydraulic Gradient Line?
6. Write down Hagen-Poiseuille equation for laminar flow
7. What are energy lines and hydraulic gradient lines?
8. Write down four examples of laminar flow.
9. What between laminar and turbulent flow.
10. What is a syphon? What are its applications?
11. What are the losses experienced by a fluid when it is passing through a pipe?
12. What is equivalent pipe?
13. What do you mean by flow through parallel pipes
14. Mention the range of Reynold’s number for laminar and turbulent flow in a pipe.
15. What is the difference between a laminar flow and turbulent flow?
16. In laminar flow through a pipe the maximum velocity at the pipe axis is 0.2m/s. Find the average velocity.
17. Define boundary layer thickness.
18. Define displacement thickness.
19. Define momentum thickness.
20. What are hydraulic gradient lines?