4HE Fluid Mechanics October-1997
Part A (20 X 2 = 40 marks)
- Give any two examples of Non-Newtonian fluid.
- Define the term "Bulk Modulus".
- State Newton's Law of viscosity.
- State the value of specific weight of mercury in kN/m3.
- Define "stream tube".
- Write the differential form of continuity equation for two-dimensional steady flow of incompressible fluid.
- What is "Drag Coefficient".
- Write the expression for head loss due to sudden expansion.
- Define the term "relative roughness" in flow through rough pipes.
- What is "hydraulic mean radius"?
- What is the optimum included angle of the divergent section of a venturi meter?
- Define the term "Stagnation pressure".
- State any two types of weirs used for flow measurement.
- Name any two metal wires used in Hot wire anemometer.
- For what application magnetic flow meter is needed?
- What factors govern the "pressure drop" in fluidized bed?
- Define the term "Design Point" of a pump.
- What is "Critical fluidization velocity"?
- What is the theoretical maximum suction lift of a centrifugal pump?
- Name any three rotary type positive displacement pumps.
Part B (5 X 12 = 60 marks)
UNIT - I
- a) Explain the significance of the property vapor pressure in the case of liquid flow. (5)
b) Show that Reynolds number is dimensionless. (3)
c) State different principles of pressure measurement (4)
- a) Explain Dimensional analysis with an example. (6)
b) How does model study is made use of in fluid flow problem. Explain with an example. (6)
UNIT - II
- a) Check whether the velocity component set given below satisfy the equation of continuity (4)
u = A sin xy
v = -A sin xy
(does not satisfy)
b) Distinguish between Laminar and Turbulent flow. What factors convert a laminar flow into turbulent. (8)
- a) Explain the growth of Boundary layer for a flow over a flat plate. Indicate Laminar, Turbulent and
Laminar sublayer of boundary layer. (6)
b) A pipe line of 120 mm diameter carries water at the rate of 30 ltr/sec. The viscosity of water is 0.012 poise and friction factor is 0.0054. Find the pressure drop over a length of 100 m. (6)
UNIT - III
- a) With a neat sketch explain the use of Pitot- Static tube. (5)
b) Water flows through a 10 cm diameter nozzle fitted in a 18 cm diameter pipe. Calculate the pressure difference between the upstream and the exit, if the discharge is 0.01 m3/s. Assume the coefficient of discharge as 0.97. (7)
- a) With a neat sketch explain the working of instruments based on Doppler effect. (6)
b) Compare the merits and demerits of orifice and venturi meter for the case of fluid flow measurements. (6)
UNIT - IV
- With a neat sketch explain the process of fluidization. State any two applications. (12)
- Draw the drag curves for regular and irregular solids and discuss. (12)
UNIT - V
- Explain the operation of an Airlift pump. Also indicate its merit over other types. (12)
- A centrifugal pump has an impeller of outer diameter 30cm. The leaving tips are radial at outlet. For a rotational speed of 1450rpm, calculate the net head developed for a manometric efficiency of 80%.(12)