JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B. Tech II Year FLUID MECHANICS AND HYDRAULIC MACHINERY Previous Question Paper (February - 2024 - R13)

Distinguish between Gauge Pressure and Vacuum pressures.

Define kinematic viscosity and write its units.

Write few minor losses in a pipe flow.

Define pitot tube and where it used.

Write the equation for work done by the jet of water striking the flat fixed plate at centre?

Write the different components of hydroelectric power plant.

What do you mean by surge tank?

What are different specific quantities in turbines?

What is priming?

Define manometric head and static head.

What is differential manometer? Explain how it works.

Find the pressure in N/m² represented by a column of 10 cm of water, 4 cm of oil of relative density 0.89 and 2 cm of mercury of specific gravity 13.6. specific weight of water is 9810 N/m².

Define the term vapour pressure. How does it vary with temperature?

A square metal plate 1.5 m side and 1.5 mm thick weighing 50 N is to be lifted through a vertical gap of 25 mm of infinite extent. The oil in the air gap has a specific gravity of 0.95 and viscosity of 2.5 Ns/m². If the metal plate is to be lifted at a constant speed of 0.1 m/s find the force and power required?

State and prove Bernoulli’s theorem. Mention its limitations.

An oil of sp. gr. 0.8 is flowing through a venturi meter having inlet diameter 20 cm and throat diameter 10cm. the oil-mercury differential manometers show a reading of 25 cm. calculate the discharge of oil through the horizontal venturi meter. Take Cd = 0.98.

Derive an expression for the discharge through a venturi meter.

Examine the head lost due to friction in a pipe of diameter 300mm and length 50m, through which water is flowing at a velocity of 3m/s using (i) Darcy formula, (ii) Chezy’s formula for which C = 60.

Describe different types of surge tank. Explain any one in detail.

A nozzle of 50 mm diameter delivers a stream of water at 20 m/s perpendicular to a plate that moves away from the jet at 5 m/s. find: (i) the force on the plate (ii) the work done, and (iii) the efficiency of jet.

How do you estimate the impact of a jet striking a moving normal plate in the direction of the jet?

What do you understand by pumped storage plant? Give its advantages and disadvantages?

What do you mean by gross head and net head. Explain different types of efficiency of a turbine?

A Pelton wheel is having a mean bucket diameter of 1 m and is running at 1000 r.p.m. The net head on the Pelton wheel is 700 m. if the side clearance angle is 15° and discharge through nozzle is 0.1 m³/s, find: (i) Power available at the nozzle and (ii) Hydraulic efficiency of the turbine.

What is a draft-tube? Why is it used in reaction turbine? Describe with neat sketch two different types of draft tubes.

A turbine is to operate under a head of 25 m at 200 r.p.m. the discharge is 9 cumec. If the efficiency is 90%. Determine (i) Specific speed of machine (ii) Power generated.

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

The internal and external diameters of the impeller of a centrifugal pump are 200 mm and 400 mm respectively. The pump is running at 1200 r.p.m. The vane angles of the impeller 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.

Explain the working of centrifugal pump with the help of a neat diagram.

Explain Cavitation. What are the effects of cavitation? Give the necessary precautions against cavitation?