JNTU PAPERS

JNTU,B.Tech I Semester Fluid Mechanics, November 2008

(Chemical Engineering)

SET-3

1. (a) What is the importance of dimensional analysis? [6]

(b) Outline the procedure for Rayleigh’s method and Buckingham method used

in dimension analysis. [10]

2. A Pipe line of 20cm dia, branches into 2 pipes having 10cm and 5cm dia respectively.

If the flow of fluid in the larger pipe is 2/3 of the main pipe and the remaining in

the smaller pipe. If the maximum velocity in either of the pipes and the main pipe

does not exceed 3m/sec. Find the velocity in each pipe and the rate of discharge

in the main pipe. [16]

3. (a) Differentiate between incompressible and compressible fluids. Give examples.

(b) Write the equations for fanning friction factor and Darcy’s friction factor.

(c) A fluid is flowing though a cylindrical pipe of radius ‘R’ explain the distribution

of velocity and shear stress. What are the force which influences the system.

[4+4+8]

4. An oil having a viscosity of 0.048 kg/ms flows through a 50 mm diameter tube at

an average velocity of 0.12 m/s . Calculate the pressure drop in 65 m of tube and

the velocity at 10mm from the tube wall. [16]

5. For an isentropic flow write the equations for the following:

(a) Velocity in a nozzle [6]

(b) Mach number [3]

(c) pressure ratio [4]

(d) Mass velocity [3]

6. Estimate the frictional pressure drop per meter of bed length for a liquid flowing

through a packed bed made of 2.2 mm diameter spheres.

DATA: Bed porosity = 0.32

Mass flux of liquid = 54000kg/m3

Liquid density = 1000kg/m3

Viscosity = 1 Cp. [16]

7. The fluidized bed expands as the superficial velocity increases and pressure drop per

unit length decreases with increase in porosity. Explain with respect to particulate

fluidization and Bubbling fluidization. [16]

8. Sulphuric acid of specific gravity 1.3 is flowing through a pipe of 5 cm ID . A thin

tipped orifice os 1cm diameter is fitted in the pipe and the differential pressure

shown by the mercury manometer is 10 m .Calculate the weight of acid flowing per

hour . Take the orifice coefficient as 0.61. [16]