A turbine is required to develop 1500 kW at 300 r.p.m. under a head of 150 m. Which of the following turbine should be used?
Pelton wheel with one nozzle
Pelton wheel with two or more nozzles
Kaplan turbine
Francis turbine
Correct Answer :
A. Pelton wheel with one nozzle
Related Questions
Which of the following pump is successfully used for lifting water from deep wells?
Centrifugal pump
Reciprocating pump
Jet pump
Air lift pump
If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge
Same quantity of liquid
0.75 Q
Q/0.75
1.5 Q
An impulse turbine is used for
Low head of water
High head of water
Medium head of water
High discharge
Which place in hydraulic turbine is most susceptible for cavitations?
Inlet of draft rube
Blade inlet
Guide blade
Penstock
The hydraulic efficiency of an impulse turbine is the
Ratio of the actual power produced by the turbine to the energy actually supplied by the turbine
Ratio of the actual work available at the turbine to the energy imparted to the wheel
Ratio of the work done on the wheel to the energy of the jet
None of the above
A double overhung Pelton wheel has
Two jets
Two runners
Four jets
Four runners
Which of the following pump is generally used to pump highly viscous fluid?
Centrifugal pump
Reciprocating pump
Air lift pump
Screw pump
The specific speed (Ns) of a centrifugal pump is given by
(N√Q)/H2/3
(N√Q)/H3/4
(N√Q)/H
(N√Q)/H5/4
In axial flow fans and turbines, fluid enters and leaves as follows
Radially, axially
Axially, radially
Axially, axially
Radially, radially
Slip of a reciprocating pump is negative, when
Suction pipe is short and pump is running at low speeds
Delivery pipe is long and pump is running at high speeds
Suction pipe is short and delivery pipe is long and the pump is running at low speeds
Suction pipe is long and delivery pipe is short and the pump is running at high speeds
For centrifugal pump impeller, the maximum value of the vane exit angle is
10° to 15°
15° to 20°
20° to 25°
25° to 30°
Francis turbine is best suited for
Medium head application from 24 to 180 m
Low head installation up to 30 m
High head installation above 180 m
All types of heads
A hydraulic ram is a device used to
Store the energy of water
Increase the pressure of water
To lift water from deep wells
To lift small quantity of water to a greater height when a large quantity of water is available at a smaller height
Francis, Kaplan and propeller turbines fall under the category of
Impulse turbines
Reaction turbines
Axial flow turbines
Mixed flow turbines
A jet of water is striking at the centre of a curved vane moving with a uniform velocity in the direction of jet. For the maximum efficiency, the vane velocity is ________ of the jet velocity
One-half
One-third
Two-third
Three-fourth
The force exerted (in Newton) by a jet of water impinging normally on a fixed plate is (where w = Specific weight of water in N/m3, a = Crosssectional area of jet in m², and V = Velocity of jet in m/s)
waV / 2g
waV / g
waV² / 2g
waV² / g
Multistage centrifugal pumps are used to
Give high discharge
Produce high heads
Pump viscous fluids
All of these
Kinematic similarity is said to exist between the model and the prototype, if both of them
Have identical velocities
Are equal in size and shape
Are identical in shape, but differ only in size
Have identical forces
The jet ratio is defined as the ratio of the
Diameter of jet to the diameter of Pelton wheel
Velocity of jet to the velocity of Pelton wheel
Diameter of Pelton wheel to the diameter of jet
Velocity of Pelton wheel to the velocity of jet
The discharge of a double acting reciprocating pump is (where L = Length of stroke, A = Cross-sectional area of piston, and N = Speed of crank in r.p.m.)
L.A.N
2 L.A.N
(L.A.N)/60
(2 L.A.N)/60
A Pelton wheel develops 1750 kW under a head of 100 metres while running at 200 r.p.m. and discharging 2500 litres of water per second. The unit speed of the wheel is
10 r.p.m.
20 r.p.m.
40 r.p.m.
80 r.p.m.
A hydraulic press is a device used
To store pressure energy which may be supplied to a machine later on
To increase the intensity of pressure of water by means of energy available from a large quantity of water at a low pressure
To lift larger load by the application of a comparatively much smaller force
All of the above
In reaction turbine, draft tube is used
To transport water downstream without eddies
To convert the kinetic energy to flow energy by a gradual expansion of the flow cross-section
For safety of turbine
To increase flow rate
The centrifugal pump preferred for a specific speed between 80 to 160 r.p.m. is
Slow speed with radial flow at outlet
Medium speed with radial flow at outlet
High speed with radial flow at outlet
High speed with mixed flow at outlet
According to fan laws, for the fans having constant wheel diameters, the power demand varies
Directly as fan speed
Square of fan speed
Cube of fan speed
Square root of fan speed
Guide angle as per the aerofoil theory of Kaplan turbine blade design is defined as the angle between
Lift and resultant force
Drag and resultant force
Lift and tangential force
Lift and drag
The water in a jet propelled boat is drawn through the openings facing the direction of motion of the boat. The efficiency of propulsion is given by
2V/(vr - v)
2V/(vr + v)
V/(vr - v)
V/(vr + v)
High specific speed of turbine implies it is
Propeller turbine
Francis turbine
Impulse turbine
None of the above
A hydraulic accumulator is a device used to store ________ energy which may be supplied to a machine later on.
Strain
Pressure
Kinetic
None of these
Which of the following pump is successfully used for lifting water to the turbines?
Centrifugal pump
Reciprocating pump
Jet pump
Air lift pump