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UNIT-1 INTRODUCTIONSYLLABUS
INTRODUCTION 12Units & Dimensions. Properties of fluids – Specific gravity, specific weight, viscosity,compressibility, vapour pressure and gas laws – capillarity and surface tension. Flowcharacteristics: concepts of system and control volume. Application of control volume tocontinuity equiation, energy equation, momentum equation and moment of momentumequation.
PART A1. 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.[APRIL’10/1]
2. The converging pipe with inlet and outlet diameters of 200 mm and 150 mm carries the oil whosespecific gravity is 0.8. The velocity of oil at the entry is 2.5 m/s, find the velocity at the exit of thepipe and oil flow rate in kg/sec. [APRIL’10/2]
3. What is the variation of viscosity with temperature for fluids? [NOV’09/1]
4. Find the height of a mountain where the atmospheric pressure is 730 mm of Hg at Normalconditions. [NOV’09/2]
5. What is meant by vapour pressure of a fluid? [APRIL’10 R-04/1]
6. Distinguish between atmospheric pressure and gauge pressure. [APRIL’10 R-04/2]
7. What are Non-Newtonian fluids? Give examples. [NOV’09 R-04/1]
8. Mention the uses of a manometer. [NOV’09 R-04/2]
9. What do you mean by absolute pressure and gauge pressure? [MAY’09 R-04/1]
10. Define the term Kinematic Viscosity and give its dimension. [MAY’09 R-04/2]
11. What is meant by continuum? [NOV’08 R-04/1]
12. State Pascal's hydrostatic law. [NOV’08 R-04/2]
13. What is specific gravity? How is it related to density? [APRIL’08 R-04/1]
14. How does the dynamic viscosity of liquids and gases vary with temperature? [APRIL’08 R-04/2]
15. How does the dynamic viscosity of (a) liquids and (b) gases vary with temperature?
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[NOV’07 R-04/1]
16. What is the difference between gauge pressure and absolute pressure? [NOV’07 R-04/2]
17. Differentiate between solids and liquids. [MAY’07 R-04/1]
18. Define the following terms : [MAY’07 R-04/2](a)Total pressure(b)Centre (or) position of pressure.
19. What is meant by capillarity? [NOV’06 R-04/1]
20. Define buoyancy. [NOV’09 R-04/2]
21. What is viscosity? What is the cause of it in liquids and in gases? [NOV’05/1]
22. State Pascal’s law. [NOV’05/2]
PART B23. 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 ofthe inlet and exit is 3 m above the free surface of the water. The pressure at the exit is 250 mm of Hgvacuum. The friction loss between the inlet, and exit of the pipe is 1/10 of the velocity head at theexit. Determine the discharge through the pipe . [APRIL’10/11(a)]
24. 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 150mm. The throat is 1.2 m from the entrance along its length. The pressure gauges fitted to the
2 2
Venturimeter if the flow is 0.20 m3/s. [APRIL’10/11(b)]
25. Explain the properties of a hydraulic fluid. [NOV’09/11(a)]
26. A 0.5 m shaft rotates in a sleeve under lubrication with viscosity 5 poise at 200 rpm. Calculate thepower lost for a length of 100 mm if the thickness of the oil is 1 mm. [NOV’09/11(b)]
27. (i) Derive Bernoulli's theorem and state its limitations. [APRIL’10 R-04/12b(i)]
28. (ii) A horizontal Venturimeter with inlet diameter 200 mm and throat diameter 100 mm is employedto measure the flow of water. The reading of the differential manometer connected to the inlet is 180mm of mercury. If Cd = 0.98 , determine the rate of flow. [APRIL’10 R-04/12b(ii)]
29. Derive continuity equation from basic principles. [NOV’09 R-04/12a (i)]
30. Derive Euler's equation of motion for flow along a stream line. What are the assumptions involved.[NOV’09 R-04/12b(ii)]
31. A horizontal pipe carrying water is gradually tapering. At one section the diameter is 150 mm andflow velocity is 1.5 m/s. If the drop in pressure is 1.104 bar at a reduced section, determine the
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diameter of that section. If the drop is 5 kN/m2, what will be the diameter — Neglect losses?[NOV’09 R-04/12b(ii)]
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32. State Bernoulli theorem for steady flow of an incompressible fluid. Derive an expression forBernoulli equation and state the assumptions made. [MAY’09/12b(i)]
33. A 15 cm diameter vertical pipe is connected to 10 cm diameterVertical pipe with a reducing socket. The pipe carries a flow of 100 1/s. At point 1 in 15 cmpipe gauge pressure is 250 kPa. At point 2 in the 10 cm pipe located 1.0 m below point 1 thegauge pressure is 175 kPa.
(1) Find whether the flow is upwards / downwards.(2) Head loss between the two points [NOV’08 R-04/12a(i)]
34. Differentiate Venturimeter andOrificemeter. [NOV’08 R-04/12a(ii)]
35. State and prove Bernoulli's Theorem [NOV’08 R-04/12b(i)]
36. Air flows through a pipe at a rate of 200 L/s. The pipe consists of two sections of diameters 20 cmand 10 cm with a smooth reducing section that connects them. The pressure difference between thetwo pipe sections is measured by a water manometer. Neglecting frictional effects, determine thedifferential height of water between the two pipe sections. Take the air density to be 1.20 kg/m3.
[MAY’08 R-04/12b(i)]37. A Pitot-static probe is used to measure the velocity of an aircraft flying at 3000 m. If the differential
pressure reading is 3 kPa, determine the velocity of the aircraft. [MAY’08 R-04/12b(ii)]38. Obtain an expression for continuity equation in Cartesian coordinates.
[NOV’07 R-04/12a(i)]39. A 300 mm x 150 mm Venturimeter is provided in a vertical pipe line carrying oil of relative density
0.9, the flow being upwards. The differential U tube mercury manometer shows a gauge deflectionof 250 mm, calculate the discharge of oil, if the coefficient of meter is 0.98. [NOV’07 R-04/12b(ii)]
40. A horizontal venture meter of specification 200 mm x 100 mm is used to measure the discharge ofan oil of specific gravity 0.8. A mercury manometer is used for the purpose. If the discharge is 100litres per second and the coefficient of discharge of meter is 0.98, find the manometer deflection.
[MAY,07 R-04/12a(ii)]
41. Derive Bernoulli's equation along with assumptions made. [MAY’07 R-04/12b(i)]
42. Mention any three applications of Bernoulli's theorem. [NOV’06 R-04/12b(i)]
43. A horizontal venturimeter with inlet diameter 200 mm and throat diameter 100 mm is employed tomeasure the flow of water. The readings of the differential manometer connected to the inlet is 180mm of mercury. If Cd= .98, determine the rate of flow. [N0V’06 R-04/12b(ii)]
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UNIT II FLOW THROUGH CIRCULAR CONDUITS
SYLLABUS
FLOW THROUG CIRCULAR CONDUITS 12Laminar flow though circular conduits and circular annuli. Boundary layer concepts. Boundary layerthickness. Hydraulic and energy gradient. Darcy – Weisbach equaition. Friction factor and Moody
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diagram. Commercial pipes. Minor losses. Flow though pipes in series and in parallel.
LAMINAR FLOW THOUGH CIRCULAR CONDUITS AND CIRCULAR ANNULI
PART A
1. Differentiate between laminar and turbulent flow. [NOV/DEC ‘2005/5]
2. Write down four examples of laminar flow. [NOV/DEC ‘2006/5]
3. Sketch velocity distribution curves for laminar and turbulent flows in a pipe. [NOV/DEC ‘2006/6]
4. What is the physical significance of Reynold's number? [MAY/JUNE ‘2007/5]
PART B
5. What is meant by critical Reynolds number. (6) [NOV/DEC ‘2006/13a(i)]
6. Obtain a relationship between shear stress and pressure gradient. (10) [NOV/DEC ‘2006/13a(ii)]
7. Derive an expression for the velocity distribution for viscous flow through a circular pipe. (8)[MAY/JUNE ‘2007/13a(i)]
8. Derive Hagen- poiseuille equation state the assumptions made. (16) [NOV/DEC ‘2005/14a]
BOUNDARY LAYER CONCEPTS
PART A
1. Define boundary layer and give its significance. [APR’10/3] [DEC ‘09/6]2. Define the term Drag and Lift[APR’09/6] [NOV ‘09/6] [NOV ‘05/6]
PART B
3. What do you mean by displacement thickness and momentum thickness? (6) [NOV ‘08/13b(ii)]
4. The velocity distribution in the boundary layer is given by u/U =y/δ, where u is the velocity at adistance y from the plate u=U at y =δ, δ being boundary layer thickness. Find the displacementthickness, momentum thickness and energy thickness. (16) [APR’10/13b]
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5. A flat plate 1.5 m x 1.5 m moves at 50 km/h in a stationary air of density 1.15 kg/m3. If thecoefficient of drag and lift are 0.15 and 0.75 respectively, determine (i) the lift force (ii) the dragforce (iii) the resultant force and (iv) the power required to set the plate in motion. (16) [NOV‘09/13b]
FLOW THROUGH PIPES
PART A
1. List any four minor losses in a pipe flow. [MAY/JUNE ‘2007/6] [JUNE’10 R-4/4]
2. What is meant by equivalent pipe? (6) [NOV/DEC ‘2006/13b(i)]3. Find the loss of head when a pipe of diameter 200 mm is suddenly enlarged to a diameter of 400
mm. Rate of flow of water through the pipe is 250 litres/s. [JUNE ‘10/4]4. List the causes of minor energy losses in flow through pipes. [DEC ‘09/3]5. What is T.E.L.? [DEC ‘09/4]6. What is Hydraulic Gradient Line? [JUNE ‘09/6]
PART B
9. Derive an expression for head loss through pipes due to friction. (16) [JUNE’10 R-4/13a]
10. Explain the losses of energy in flow through pipes. (16) [DEC ‘09/12a]
11. Determine the equivalent pipe corresponding to 3 pipes in series with lengths and diametersL1,L2,L3,d1,d2,d3 respectively. (16) [DEC ‘09/12b]
12. The velocity of water in a pipe 200mm diameter is 5m/s. The length of the pipe is 50m. Find theloss of head due to friction, if f= 0.08. (4) [NOV/DEC ‘2005/14b(ii)]
13. The rate of flow of water through a horizontal pipe is 0.25 m3/sec.The diameter of the pipe which is20 cm is suddenly enlarged to 40 cm. The pressure intensity in the smaller pipe is 11.772 N/cm2.
Determine :Loss of head due to sudden enlargement,Pressure intensity in larger pipe,Power loss due to enlargement. (9) [JUNE ‘09/13a(i)]
14. An oil of sp.gravity 0.7 is flowing through a pipe of diameter 30 cm at the rate of 500 litres/sec.Find the head lost due to friction and power required to maintain the flow for a length of 1000 m.Take υ= 0.29 stokes. (8) [JUNE ‘09/13b(ii)]
15. Three pipes of 400 mm, 350 mm and 300 mm diameter are connected in series between tworeservoirs. With a difference in level of 12 m. Friction factor is 0.024, 0.021 and 0.019 respectively.The lengths are 200 m, 300 m and 250 m. Determine flow rate neglecting minor losses.(8) [DEC ’09 R-4/13a(ii)]
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