Jawaharlal Nehru University (JNU) 2008 B.Tech Chemical Engineering MOMENTUM TRANSFER - Question Paper

B.Tech I Semester Regular Examinations, November 2008
MOMENTUM TRANSFER
(Chemical Engineering)

Time: three hours Max Marks: 80

ans any 5 ques.

All ques. carry equal marks

1. Write short notes on:

(a) Unit operation

(b) Dimensionless formula

(c) Dimensional formula. [6+5+5]

2. Water is pumped at the rate of 200 lit/s through a 30 cm pipe upto a hill top. If
the pump maintains a pressure of 150 kN/m2 at the hill top at an elevation of 45
m, What is the pressure at the foot hills at zero elevation. Neglecting losses, What
is the power needed to pump the water? [16]

3. Under conditions of laminar flow , the friction factor is provided by 16/ NRe .Derive
an expression for the pressure drop per unit length in terms of the pipe diameter,
‘d’, the avg. velocity ‘u’, the density and the viscosity of the fluid. [16]

4. (a) Derive the formula of continuity of compressible fluids. State the assumptions
clearly.

(b) Methane gas is being pumped through a 305m length of 52.5mm diameter
steel pipe at a rate of 41.0kg/m2-s.The inlet and outlet pressure is 345kPa
abs and 298kPa. presume isothermal flow at 288.8K.Calculate the maximum
velocity that can be found at these conditions. [10+6]

5. (a) Write Erguns formula and comment on its applicability.

(b) Differentiate free and hindered settling. [16]

6. Distinguish particulate and aggregative fluidization. [16]

7. discuss the working of a centrifugal pump with neat sketch. [16]

8. A lube oil(specific gravity 0. is flowing through a 15 cm steel pipe at 1500 LPM.
A 10 cm orifice attached to a mercury manometer is placed in the pipe line and the
orifice coefficient may be taken as 0.62. If the manometer leg is inclined at an angle
of 300 to the horizontal, what would be the manometer studying along the sloping
leg?

Earning:   Approval pending.