4HE Fluid Mechanics April - 1999

Part - A (Answer ALL questions.) 20 x 2 = 40 Marks

  1. Define Newtonian fluid.
  2. What is "vapour pressure".
  3. Define kinematic viscosity.
  4. Write the unit of power in M.L.T. system.
  5. Define 'stream tube'.
  6. What is 'form drag'?
  7.  State the use of Reynolds number in fluid flow.
  8. Indicate a possible velocity profile in "Turbulent flow".
  9. Define the term 'Mach number'.
  10. State Euler's equation for ideal fluid flow.
  11. Why the length of divergent section of a venturimeter is much longer than its convergent section.
  12. Define the term "Coefficient of Contraction".
  13. Write the expression for discharge through a V-notch with an included angle of q
  14. What are the types of Hot-wire anemometer used in practice?
  15. Suggest a flow meter for measuring slurry flow in a closed pipeline.
  16. Define the term "Fluidization".
  17. Name any two types of positive displacement pump.
  18. Name any three applications for continuous fluidization.
  19. Define the term "shut off head" of a centrifugal pump.
  20. Which fan produce a high static pressure rise, a backward curved fan or a forward curved fan.
  21. Part - B

  22. (a) (i) Derive an expression for capillary rise of water in a small tube. (5)
  23. (ii) Water has a surface tension of 0.4 N/m. In a 3 mm diameter vertical tube if the liquid rises 6 mm above the liquid outside the tube, calculate the contact angle. (7)


    (b) (i) Define Geometric and Kinematic similarity. (4)

    (ii) A U - tube differential mercury manometer is connected between two pipes X and Y. Pipe X contains carbon tetra chloride (Sp.gr. 1.59) under a pressure of 103 kN/m2 and pipe Y contains oil (Sp.gr. 0.8) under a pressure of 172 kN/m2. Pipe X is 2.5 m above pipe Y. Mercury level in the limb connected to pipe X is 1.5 m below the centerline of pipe Y. Find the manometer reading as shown by a centimeter scale attached to it. (8)

  24. (a) (i) Explain the concept velocity potential and stream function.(4)
  25. (ii) Water flows through a horizontal conical pipe. The diameter at larger end is 1.3 m and that at smaller end is 0.7 m. The pressure head at the smaller end is 5 m of water and discharge is 3.5 m3/sec. Calculate the velocities at the two ends and pressure head at larger end. (8)


    (b) (i) Explain the method of reducing skin friction drag. (4)

    (ii) A medium lubricating oil of sp.gr. 0.86 is pumped through 300 m horizontal pipe of diameter 50 mm at a rate of 1.24 lit/sec. If the pressure drop is 0.2 MPa find the absolute viscosity of oil. (8)

  26. (a) Derive an expression for coefficient of discharge of a venturimeter.
  27. Or

    (b) With a neat sketch explain the working principle of a Hot-film anemometer.

  28. (a) Describe the methods of estimating pressure drop through a packed bed.
  29. Or

    (b) Describe the general properties of fluidized bed.

  30. (a) Describe the working principle of any one type rotary pump with a neat sketch.
  31. Or

    (b) (i) Explain the various performance curves of a centrifugal pump.

    (ii) Briefly explain the method of selecting a pump for a given application.