Andhra University 2007 B.E fluid mechanics - exam paper

II Year B.E./B.Tech Degree exam
FLUID MECHANICS

(Chemical Engineering)

Time: three hours Max.Marks: 75

ques. one is compulsory

ans any 4 from ques. two to 8

All ques. carry equal marks

1. Write briefly about the subsequent : (5 x three = 15)

a) likeness

b) kinds of turbulence

c) Boundary layer separation

d) Drag

e) Valves

2. a) Derive an expression for the estimation of pressure drop

in a centrifuge.

b) A centrifuge bowl 250 mm internal diameter is turning

at 4000 rpm. It contains a layer of chlorobenzene

50 mm thick. If the density of chlorobenzene is

1109 kg/m3 and the pressure is exerted on the wall of

the centrifuge bowl?

3. a) describe boundary layer and explain its formation.

b) With the help of neat sketches, discuss the laminar and

turbulent flows in boundary layers.

c) explain boundary layer separation and wake formation.

4. a) discuss the difference ranging from a fan, a blower and a

compressor.

b) define with a neat diagram, the working principle of

a rotary pump.

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5. Benzene at 380C is pumped from a reservoir at a rate of 9

m3/h and discharged against a gauge pressure of 345 kPa.

The discharge line is made with 1.5 inch ID pipe. The discharge

point is 10 ft and the pump suction is four ft above the level in the

reservoir. The friction in the suction line is 3.5 kPa and in the

discharge line is 38 kPa. The density of benzene is 865 kg/

m3 and its vapor pressure is 26 kPa. compute the developed

head of the pump and the total power input assuming the

efficiency of the pump to be 60 percent.

6. a) elaborate the advantages and disadvantages of venturi

meter over orifice meter?

b) A sharp edged orifice having a diameter of 0.0566 m is

installed in a 0.1541 m diameter pipe through which oil

having a density of 878 kg/m3 and a viscosity of 4.1 cP

is flowing. The pressure difference is 93 kPa. compute

the volumetric flow rate in m3/s? presume C0 = 0.61.

7. a) What is terminal velocity? Differentiate ranging from

hindered settling and free settling.

b) Urea pellets are made by spraying drops of molten urea

into cold gas at the top of a tall tower and allowing the

material to solidify as it falls. Pellets six mm in diameter

are to be made in a tower 25 m high containing air at

200C. The density of urea is 1330 kg/m3. What would

be the terminal velocity of the pellets, assuming freesettling

conditions?

8. discuss in detail different pipe fittings employed in chemical

process industries.

Earning:   Approval pending.