No. of Printed Pages: 7 IBEToOS71
nlPwMA IN CIVIL ENGINEERING (DCLE(G» I DIPLOMA IN MECHANlCAL
(DME)
Term-End Examjnation
00592
December,2016
BET.037 FLUID MF;CMANIC$
Time: 2 hours Ma%imum Marks: 70
Note: All q1,lestioTUJ are compulsory. Use of scientific ca4culator is permitted.

1. Choose the correct answer from the given four alternatives. . 7x2=14 Power transmitted through pipes will be maximum when head loss due to friction 1/2 total head at the inlet of the pipe.

(ii) head loss due to friction total head at the inlet of the pipe.

(iii) head loss due to friction total head at the inlet of the pipe.
head loss due to friction 1/3 total head at the inlet of the pipe.
The coefficient of discharge in terms of Cy and Cc is Cd=Cv/Cc

(ii) Cd=Cc/Cv

(iii) Cd Cy x Cc

(iv) None of the above Dynamic viscosity has the dimension as

(ii)

(iii) Newton's law of viscosity states that shear stress is directly proportional to the velocity

(ii) shear stress is directly proportional to the velocity gradient

(iii) shear stress is directly proportional to shear strain

(iv) shear stress is directly proportional to the viscocity A streamline is a line drawn normal to the velocity vector at every point

(ii) such that the streamline divides the passage into equal number of parts

(iii) which is along the path of a particle

(iv) tangent to which is in the direction of the velocity vector at every point Capillarity rise and depression phenomena depend upon the size of the tube

(ii) depend solely upon the surface tension of the liquid

(iii) depend upon the surface tension of the liquid as well as the material of the tube

(iv) depend upon the pressure difference between the liquid and the environment Bernoulli's theorem deals with the law of conservation of mass

(ii) momentum

(iii) energy

None of the above

2. Answer any two of the following: 2x7=14 Enumerate Newton's law of viscosity. Explain the importance of viscosity in fluid motion. What is the effect of temperature on viscosity of water and that of air If the velocity distribution over a plate is given by

u 2/3 y y^2

in which u is the velocity in m/sec at a distance y metres above the plate, determine the shear stress at y and y 0.15 m. Take dynamic viscosity of the fluid as 8.63 poise. What is the bulk modulus of elasticity of Ii liquid which is compressed in a cylinder from a volume of 0.0125 m3 at 80 N/cm2 pressure to a volume of 0.0124 m3 at 150 N/m2 pressure

3. Answer any two of the following: 2x7=14 Differentiate between the following: Dynamic viscosity and Kinematic viscosity .

(ii) Absolute and Gauge pressure

(iii) Simple and Differential manometers

(iv) Centre of gravity and Centre of buoyancy An open tank Contains water up to a depth of 2 m and above it an oil of specific gravity 0.9 for a depth of 1 m. Find the pressure intensity at the interface of the two liquids, and

(ii) at the bottom of the tank. A wooden block of width 2 depth 1.5 m and length 4 m floats horizontally in wat4»'. Find the volume of water displaced and the position of centre of buoyancy. 'The specific gravity of the wooden block is 0.7.

4. Answer any two of the following 2x7=14 State Bernoulli's theorem for steady flQw of an incompressible fluid. Derive an expression for Bernoulli's equation from the first principle.
A pipe, through which water is flowing, is having diameters 20 cm and 10 em at the cross-sections 1 and 2 respectively. The velocity of water at section 1 is given as 4.0 m/s. Find the velocity head at sections 1 and 2 and also find the rate of discharge. A pipe 450 mm in diameter, branches into two pipes and of diameters 300 mm and 200 mm respectively as shown in Figure <img src='./qimages/8541-4(c).jpg'>
Figure 1

If the average velocity in the 450 mm diameter pipe is 3 find
the discharge through the 450 mm diameter pipe, and

(ii) the velocity in the 200 mm diameter pipe, if the average velocity in the 300 mm diameter pipe is 2.5 m/s.

5. Write short notes on any four of the following: Turbulent Flow
Steady Flow Compressible Flow Syphons Loss of Head at Bends
Orifice Meter