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.
Distinguish between specific weight and specific gravity.
(2 marks)
00
1.b.
Explain bulk modulus and compressibility.
(3 marks)
00
1.c.
What is velocity potential function?
(2 marks)
00
1.d.
What is meant by liquids in relative equilibrium?
(3 marks)
00
1.e.
What is broad crested weir?
(2 marks)
00
1.f.
Explain Navier Stoke's equation along with its significance.
(3 marks)
00
1.g.
List out all major and minor losses.
(2 marks)
00
1.h.
Explain what water hammer is.
(3 marks)
00
1.i.
Explain Prandtl boundary layer equations.
(2 marks)
00
1.j.
What is magnus effect? Explain.
(3 marks)
00
PART-B
2.a.
Differentiate between:
i) Liquids and Gases
ii) Cohesion and Adhesion
iii) Real fluid and Ideal fluid
iv) Compressible and Incompressible fluids.
(5 marks)
00
2.b.
In a stream of glycerin in motion, the velocity gradient at a certain point is 0.30 meters per sec per, meter. Calcutate the shear stress at the point if the mass density of the liquid is 1275 kg/m³ and the kinematic viscosity is 6.30 x 10-4 sq.m/sec.
(5 marks)
00
OR
3.a.
Distinguish between (i) standard and local atmospheric pressures, (ii) barometric
pressure and absolute pressure and (iii) absolute pressure and gauge pressure.
(5 marks)
00
3.b.
Determine the intensity of shear of an oil having viscosity $=1.2$ poise and is used foe lubrication in the clearance between a 10 cm diameter shaft and its journal. bearing. The clearance is 1.0 mm and shaft rotates at 200 rpm .
(5 marks)
00
4.a.
Define the equation of continuity. Obtain an expression for continuity equation
for a three dimensional flow.
(5 marks)
00
4.b.
Water is flowing through a pipe having diameters 30 cm and 15 cm at the bottom and upper end respectively. The intensity of pressure at the bottom end is 29.43 $\mathrm{N} / \mathrm{cm}^{2}$ and the pressure at the upper end is 14.715 $\mathrm{N} / \mathrm{cm}^{2} .$ Determine the difference in datum head if the rate of flow through pipe is 50 $\mathrm{lit} / \mathrm{s}$ .
(5 marks)
00
5
Write short note on:
a) Buoyancy and flotation
b) Circulation and Vorticity
c) Flow net.
(10 marks)
00
6.a.
Derive Bernoulli's equation for the flow of an incompressible frictionless fluid
from consideration of momentum.
(5 marks)
00
6.b.
A $45^{\circ}$ reducing bend is connected in a pipe line, the diameters at the inlet and
outlet of the bend being 40 cm and 20 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
OR
7.a.
Explain the momentum equation along with its applications.
(5 marks)
00
7.b.
A 10 $\mathrm{cm}$ by 6 cm orifice meter is used to measure the discharge of bromine. If the
pressure difference across the orifice plate is 18250 $\mathrm{N} / \mathrm{m}^{2}$ , determine the discharge in lit/m. Assume Cd = 0.64. Specify gravity of bromine = 3.1.
(5 marks)
00
8.a.
Obtain an expression for head loss. due to friction in the pipe. List all the
assumptions made in the derivation.
(5 marks)
00
8.b.
Explain how the following flow problems are analyzed:
(i) Series pipe connection and (ii) parallel pipe connection.
(5 marks)
00
OR
9.a.
Describe Reynolds experiment with a neat sketch.
(5 marks)
00
9.b.
A horizontal pipe of diameter 400 $\mathrm{mm}$ is suddenly contracted to a diameter of
200 $\mathrm{mm}$ . The pressiure intensities in the large and smaller pipe are given as 14.715 $\mathrm{N} / \mathrm{cm}^{2}$ and $12,753 \mathrm{N} / \mathrm{cm}^{2}$ respectively. If $\mathrm{Ce}=0.62,$ find the loss of head due to contraction Also determine the vate of flow of water.
(5 marks)
00
10.a.
Describe Von-Karman's momentum integral equation. What is the significance of
it?
(5 marks)
00
10.b.
Explain what is meant by drag, lif and Magnus effect.
(5 marks)
00
OR
11.a.
What do you mear by boundary layer separation, What is the effect of pressure
gradient on boundary layer separation?
(5 marks)
00
11.b.
How will you find the drag on a flat plate due to laminar and turbulemt boundary
layers?
(5 marks)
00