In a centrifugal pump, the regulating valve is provided on the
Casing
Delivery pipe
Suction pipe
Impeller
Correct Answer :
B. Delivery pipe
Related Questions
The impeller of a centrifugal pump may have
Volute casing
Volute casing with guide blades
Vortex casing
Any one of these
The overall efficiency of a reaction turbine is the ratio of
Power produced by the turbine to the energy actually supplied by the turbine
Actual work available at the turbine to the energy imparted to the wheel
Workdone on the wheel to the energy (or head of water) actually supplied to the turbine
None of the above
The ratio of quantity of liquid discharged per second from the pump to the quantity of liquid passing per second through the impeller is known as
Manometric efficiency
Mechanical efficiency
Overall efficiency
Volumetric efficiency
Dynamic 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
None of the above
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.
By fitting an air vessel to the reciprocating pump, there is always a saving of work done and subsequently saving of power. The saving in case of a double acting reciprocating pump is
39.2 %
48.8 %
84.8 %
88.4 %
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, the horse power required will be
Same
0.75 B.H.P.
B.H.P./0.75
1.5 B.H.P.
The Fourneyron turbine is _________ reaction turbine.
An axial flow
An inward flow
An outward flow
A mixed flow
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°
In an outward flow reaction turbine
The water flows parallel to the axis of the wheel
The water enters at the centre of the wheel and then flows towards the outer periphery of the wheel
The water enters the wheel at the outer periphery and then flows towards the centre of the wheel
The flow of water is partly radial and partly axial
In a Kaplan turbine runner, the numbers of blades are generally between
2 to 4
4 to 8
8 to 16
16 to 24
A turbine develops 10000 kW under a head of 25 metres at 135 r.p.m. Its specific speed is
175.4 r.p.m.
215.5 r.p.m.
241.5 r.p.m.
275.4 r.p.m
Puck up the wrong statement about centrifugal pump
Discharge a diameter
Head a speed²
Head a diameter
Power a speed⁴
Reaction turbines are used for
Low head
High head
High head and low discharge
Low head and high discharge
The function of guide vanes in a reaction turbine is to
Allow the water to enter the runner without shock
Allow the water to flow over them, without forming eddies
Allow the required quantity of water to enter the turbine
All of the above
The specific speed of a turbine is given by the equation
N√P / H3/2
N√P / H²
N√P / H5/4
N√P / H3
Impulse turbine is generally fitted
At the level of tail race
Little above the tail race
Slightly below the tail race
About 2.5 m above the tail race to avoid cavitations.
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
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 power of the wheel is
0.25 kW
0.75 kW
1.75 kW
3.75 kW
Reciprocating pumps are no more to be seen in industrial applications (in comparison to centrifugal pumps) because of
High initial and maintenance cost
Lower discharge
Lower speed of operation
Necessity of air vessel
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 power produced by the reaction turbine is ________ to the head of water.
Directly proportional
Inversely proportional
4th power
None of these
The Thomson's turbine is __________ reaction turbine.
An axial flow
An inward flow
An outward flow
A mixed flow
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
The flow ratio in case of Francis turbine varies from
0.15 to 0.3
0.4 to 0.5
0.6 to 0.9
1 to 1.5
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
In a single casing, multistage pump running at constant speed, the capacity rating is to be slightly lowered. It can be done by
Designing new impeller
Trimming the impeller size to the required size by machining
Not possible
Some other alterations in the impeller
The angle of taper on draft tube is
Greater than 15°
Greater than 8°
Greater than 5°
Less than 8°
According to fan laws, at constant speed and capacity, the pressure and power vary
Directly as the air or gas density
Inversely as square root of density
Inversely as density
As square of density
The mechanical efficiency of an impulse turbine is
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