### 4HE Fluid Mechanics April-1997

Part A (20 X 2 = 40 marks)

1. Mass and weight of a body are differentiated in terms of the ____________ acting on it.
2. Viscosity may be described as the ratio between ____________ and ____________.
3. Paint is ____________ by nature.
4. Torricelli's equation is stated as ____________.
5. Pressure of a liquid can be converted into the ____________ of the liquid by dividing by the corresponding density.
6. Water is not a ____________ liquid.
7. The compressible fluid used in an inverted manometer is ____________.
8. The unit for Poise is ____________.
9. An ideal fluid has no ____________ or ____________.
10. The length required to establish fully developed flow in the entire cross section of the pipe is called ____________.
11. The skin friction drag may be expressed by the equation F/?.
12. For scaling up laboratory data to an industrial scale, the three similarities are ____________, ____________ and ____________.
13. Froude number is expressed as a ratio between ____________ and ____________ forces.
14. A pitot tube is used to measure ____________ velocities in a pipe line.
15. The forces acting on an aeroplane flying at a constant speed at a given altitude are ____________, ____________ and ____________.
16. The forces acting on a particle in a batch fluidized bed at steady state are ____________, ____________ and ____________.
17. Ergun's equation is useful in predicting the ____________ in a packed column.
18. In a centrifugal pump, water enters at the ____________ of the impeller.
19. Viscous liquids are transported by a ____________ pump.
20. One seventh power law states ? = ?
21. Part B (5 X 12 = 60 marks)

22. (a) State the types of fluids with suitable examples that are not Newtonian by nature. In a neat diagram mark the relation between shear stress and velocity gradient.
23. Or

(b) How does a U - tube manometer function? Derive an expression for (P1 - P2) in terms of measurable quantities.

24. (a) Define:
1. Form drag
2. Skin drag
3. Boundary layer
4. Compressible flow
5. Smooth and rough pipes.

Or

(b) Derive Hagen-Poiseuilles equation, highlighting the assumptions made.

25. (a) Explain the working of a rotameter with a neat sketch. Apply Bernoulli's principle and derive an expression for Q.
26. Or

(b) (i) With neat functional diagrams, explain the instruments used for measure of flow of gases through pipelines 100 cm long and 60 cm in diameter.

(ii) Water is draining from a tank through a hole developed at the bottom. Calculate the coefficient of discharge if the head of the water is maintained at 5 cm and 330 cc of water is collected in 30 sec. The hole dia. = 0.48 cm.

(0.614)

27. (a) Write an explanatory note on fluidized beds. Derive an expression for pressure drop in such units.
28. Or

(b) (i) State the industrial applications of fluidized beds.

(ii) With a neat diagram, explain the relationships between pressure drop and modified Nre.

29. (a) (i) Explain with neat sketches the working of a centrifugal pump. What are the advantages and demerits of such a pump?

(ii) Plot a graph to explain the characteristics of such a pump.

Or

(b) (i) Describe the working of an airlift pump. Give a neat sketch.

(ii) Calculate the BHP of a centrifugal pump from the data given below:

• Suction head = 2.54 cm Hg
• Discharge head = 20 kg/cm2
• Weight of water collected in 30 sec = 15 kg.

(979.3 Watt)