JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech II FLUID MECHANICS II Previous Question Paper (December - 2018 - R16)

What is most economical channel?

Give classification of surges.

What is meant by dimensionally homogeneous equation?

What is the need for model studies?

What do you know by hydrodynamic force?

State and explain angular momentum principle.

Draw the layout of a hydropower station.

Explain the need of a surge tank.

Distinguish between firm and secondary power.

Explain why reciprocating pumps are not in common use.

Give complete classification of the different types of open channel flow.

Water flows uniformly at a depth of 1.2 meters in a rectangular canal 3 metres wide laid at a slope of 1 metre per 1000 metres. What is the mean shear stress on the sides and bottom of the canal. Based on the Reynolds and Froude numbers, determine the type of flow in the canal. Take Chezy C as 70 and kinematic viscosity is 10^-6 m^2/s.

Explain the terms rapidly varied flow, gradually varied flow and spatially varied flow.

A trapezoidal channel with side slopes of 1:1 has to be designed to convey 10 m^3/s at a velocity of 2 m/s, so that the amount of concrete lining for the bed and sides is the minimum.

i) Calculate the area of lining required for one meter length of the canal.

ii) If the Rugosity coefficient n = 0.015, calculate the bed slope of the canal for uniform flow.

What are the two systems adopted to express derived units?

Write an account of the role of model testing in the analysis of hydraulic structures.

What are the considerations influencing the selection of a scale for a model.

Find an expression for the efficiency of a series of moving curved vanes when a jet of water strikes the vanes at one of its tips. Prove that maximum efficiency is when u=V and the value of maximum efficiency is 50%.

A jet of water having a velocity of 30 m/s strikes a curved vane, which is moving with a velocity of 15 m/s. The jet makes an angle of 30° with the direction of motion of vane at inlet and leaves at an angle of 120° to the direction of motion of vane at outlet. Calculate:

(i) Vane angles, if the water enters and leaves the vane without shock,

(ii) Work done per second per unit weight of water striking the vanes per second.

Using the impulse-momentum principle, derive an expression for the force exerted by a moving jet of fluid on a stationary curved vane.

Water impinged on a series of curved vanes entering at 30° and leaving at 120° to the direction of motion of vanes. The velocity of water at entry is 30 m/s and the vane velocity both at its inlet and exit tips is 15 m/s. Determine the vane angles for no shock conditions, the work done per unit weight of fluid and the hydraulic efficiency of the system. Neglect friction effects.

Compare and contrast impulse and reaction turbines.

A Kaplan turbine working under a head of 25 m develops 16000 kW shaft power. The outer diameter of the runner is 4 m and hub diameter is 2 m. The guide blade angle is 35°. The hydraulic and overall efficiency are 90% and 85% respectively. If the velocity of whirl is zero at outlet, determine runner vane angles at inlet and outlet, and speed of turbine.

Explain, the principle and working of a Pelton wheel with a neat sketch.

Draw a neat diagram of Kaplan turbine and explain its working.

Define a centrifugal pump. Explain the working of a single-stage centrifugal pump with sketches.

The internal and external diameters of the impeller of a centrifugal pump are 300 mm and 600 mm respectively. The pump is running at 1000 r.p.m. The vane angles at inlet and outlet are 20° and 30° respectively. The water enters the impeller radially and velocity of flow is constant. Determine the work done by the impeller per unit weight of water.

Obtain an expression for the work done by impeller of a centrifugal pump on water per second per unit weight of water.

A centrifugal pump is to discharge 0.12 m^3/s at a speed of 1400 r.p.m. against a head of 30 m. The diameter and width of the impeller at outlet are 25 cm and 5 cm respectively. If the manometric efficiency is 75%, determine the vane angle at outlet.