JNTU B.Tech III MECHANICS OF FLUIDS AND HYDRAULIC MACHINES Previous Question Paper (May - 2018 - R13)

What is compressibility and bulk modulus?

List out different fluid properties along with their significance.

What do you mean by laminar and turbulent flows?

Distinguish between fluid statics and kinematics.

Distinguish between Orifice meter and venturi meter.

What is the concept of boundary layer?

What is geometric similarity?

What is cavitation?

Give the classification of pumps.

What is meant by indicator diagram?

Derive an expression for the variation of density of a fluid in terms of its bulk modulus and pressure change.

A long steel rod of 2 cm diameter inclined at 60 deg with the horizontal is smeared with glycerin of viscosity 8.5 poises. A smooth brass sleeve of internal diameter 2.05 cm and length 30 cm slides concentrically down along the rod. If the weight of the sleeve is 12.5 N, determine the uniform speed of motion. Assume that the annular space between the rod and sleeve is completely filled with the lubricant.

Distinguish between: i) Standard and local atmospheric pressures, ii) Barometric pressure and absolute pressure and iii) Absolute pressure and gauge pressure.

Explain the working of a Bourdon pressure gauge.

Derive Bernoulli’s equation for the flow of an incompressible frictionless fluid from consideration of momentum.

A 45 deg reducing bend is connected in a pipe line, the diameters at the inlet and outlet of the bend being 40 cm and 20 cm respectively. Find the force exerted by water on the bend if the intensity of pressure at inlet of bend is 21.58 N/cm². The rate of flow of water is 500 litres/s.

Discuss the limitations of Bernoulli’s equation. Although the validity of Bernoulli’s equation is limited to frictionless flows, why is it used to find solution to many real fluid flow problems.

A 100 mm diameter pipe carries oil of specific gravity 0.8 which flows with a velocity of 2 m/s. At another section of the pipe, the diameter is 50 mm. Determine the mass flow rate of oil through the pipe and velocity of oil at the smaller section.

What do you understand by pipes in series, pipes in parallel and equivalent pipe. Explain with neat sketches.

A venturimeter is used for measurement of discharge of water in horizontal pipe line. If the ratio of upstream pipe diameter to that of throat is 2:1, upstream diameter is 300 mm, the difference in pressure between the throat and upstream is equal to 3 m head of water and loss of head through meter is one-eighth of the throat velocity head, calculate the discharge in the pipe.

What do you understand by the terms: major energy loss and minor energy losses in pipes.

Find the velocity of flow of oil through a pipe, when the difference of mercury level in a differential U-tube manometer connected to the two tappings of the pitot-tube is 15 cm. Take specific gravity of oil = 0.8 and co-efficient of pitot-tube as 0.98.

Explain with the help of a diagram, the essential features of a Kaplan turbine installation.

A Francis turbine has to be designed to give an output of 500 MHP under a head of 80 m. The rotational speed is 700 rpm. Determine the main dimensions of the runner and the guide vane and runner vane angles assuming the following data: hydraulic losses = 10%, flow ratio = 0.15, ratio of inner to outer diameters = 0.5, ratio of width to diameter at inlet = 0.1, overall efficiency = 82% and area blocked by thickness of runner vanes=5%.

Define the terms: i) Priming ii) Manometric efficiency iii) Net positive suction head.

A centrifugal pump running at 1220 rpm delivers 0.25 m³/s against a head of 20 m. Calculate the discharge, head and power if the speed is increased to 1440 rpm.

What is the function of the following in a centrifugal pump: i) Foot valve ii) Impeller iii) Delivery valve

What are the methods of converting high velocity at impeller periphery in pumps to high pressure?