0
438views
Fluid Mechanics Question Paper - Dec 17 - Civil Engineering (Semester 3) - Jawaharlal Nehru Technological University (JNTUH)
1 Answer
0
0views

Fluid Mechanics - Dec 17

Civil Engineering (Semester 3)

Total marks: 80
Total time: 3 Hours
INSTRUCTIONS
(1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Draw neat diagrams wherever necessary.

PART-A

1.a. State and explain Pascal's law.
(2 marks) 00

1.b. Differentiate centre of gravity and centre of pressure.
(3 marks) 00

1.c. Differentiate fluid statics and kinematics.
(2 marks) 00

1.d. State and explain continuity equation.
(3 marks) 00

1.e. Distinguish between surface and body forces.
(2 marks) 00

1.f. Describe the classification of orifices.
(3 marks) 00

1.g. Explain how flow takes place in closed conduits.
(2 marks) 00

1.h. Explain HGL and TEL with a neat sketch.
(3 marks) 00

1.i. Give Navier Stoke's equation.
(2 marks) 00

1.j. Distinguish between drag and lift.
(3 marks) 00

PART-B

2.a. Define Viscosity, Surface tension and $\mathrm{y}$ apor Pressure and explain their influence on fluid motion.
(5 marks) 00

2.b. An open tank contains water up to a depth of 1.5 $\mathrm{m}$ and above it an oil of sp.gr.0.8 for a depth of 2 $\mathrm{m}$ . Find the pressure intensity: (i) at the interface of the two liquids, and (ii) at the bottom of the tank.
(5 marks) 00

OR

3.a. Distinguish between:

i) specific weight and specific volume,

ii) density and relative density and

iii) adhesion and cohesion.

(5 marks) 00

3.b. 10 $\mathrm{m}^{3}$ of carbon tetrachloride reduces in volume by 0.11 percent when subjected to certain pressure increase. If the bulk modulus of the fluid is $1.145 \times 10^{6} \mathrm{N} / \mathrm{m}^{2}$ ,the original specific weight is $15,750 \mathrm{N} / \mathrm{m}^{3}$ , calculate the increase in pressure and the final specific weight.
(5 marks) 00

4.a. Distinguish between: (i) Steady flow and un-steady flow, (ii) Uniform and non-unifrom flow (iii) Compressible and incompressible flow, (iv) Rotational and Irrorational flow (v) Laminar and turbulent flow.
(5 marks) 00

4.b. A 100 $\mathrm{mm}$ diameter pipe carries oil of specific gravity 0.8 which flows with a velocity of 2 $\mathrm{m} / \mathrm{s}$ . At another section of the pipe, the diameter is 50 $\mathrm{mm}$ . Determine the mass flow rate of oil through the pipe and velocity of oil at the smaller section.
(5 marks) 00

OR

5.a. Explain stream function and velocity potential function.
(5 marks) 00

5.b. Examine whether the following velocity components represent a possible incompressible two-dimensional flow. If so, state whether the flow is rotational or irrotational u = 2x + y and v = x -2y.
(5 marks) 00

6.a. What is a Venturimeter? Derive an expression for the discharge through a Venturimeter.
(5 marks) 00

6.b. An orifice-meter with orifice diameter 15 $\mathrm{cm}$ is inserted in a pipe of 30 $\mathrm{cm}$ diameter. The pressure gauges fitted upstream and downstream of the orifice meter give readings of 14.715 $\mathrm{N} / \mathrm{cm}^{2}$ and 9.81 $\mathrm{N} / \mathrm{cm}^{2}$ respectively. Find the rate of flow of water through the pipe in literss. Take $\mathrm{Cd}=0.6 .$
(5 marks) 00

OR

7.a. Derive Bernoulli's equation for the flow of an incompressible trictionless fluid from consideration of momentum.
(5 marks) 00

7.b. A $45^{0}$ reducing bend is connected in a pipe line, the diameters at the inlet and outlet of the bend being 40 $\mathrm{cm}$ and 20 $\mathrm{cm}$ respectively. Find the force exerted by water on the bend if the intensity of pressure at inlet of bend is 21.58 $\mathrm{N} / \mathrm{cm}^{2} .$ The rate of flow of water is 500 L/sec.
(5 marks) 00

8.a. What do you mean by'equivalent pipe. Obtain an expression for equivalent pipe.
(5 marks) 00

8.b. A pipe of diameter 300 mm and length 1000 m connects two reservoirs, having difference of water levels as 15 m. Determine the discharge through the pipe. If an additional pipe of water levels as 15 m. Determine the discharge through the pipe. If an additional pipe of diameter 300 mm and length 600 m is attached to the last 600 m length of the existing pipe, find the increase i the discharge. Take f = 0.02 and neglect minor losses.
(5 marks) 00

9.a. Show that the loss of head due to sudden expansion in pipe line is a function of velocity head.
(5 marks) 00

9.b. Describe the characteristics of laminar and turbulent flows.
(5 marks) 00

10.a. What is meant by boundary layer separation? What is the effect of pressure gradient on boundary layer separation?
(5 marks) 00

10.b. Explain the factors affecting boundary layer thickness.
(5 marks) 00

OR

11.a. Explain the terms boundary layer, familiar sub-layer and point of separation.
(5 marks) 00

11.b. Describe the characteristics of boundary layer with reference to flow over a flat plate.
(5 marks) 00

Please log in to add an answer.