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
Correct Answer :
D. To lift small quantity of water to a greater height when a large quantity of water is available at a smaller height
Related Questions
The runaway speed of a hydraulic turbine is the speed
At full load
At which there will be no damage to the runner
Corresponding to maximum overload permissible
At which the turbine will run freely without load
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 depth of the bucket for a Pelton wheel is generally ________ the diameter of jet.
Equal to
1.2 times
1.8 times
Double
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 %
Discharge (Q) of a centrifugal pump is given by (where D = Diameter of impeller at inlet, b = Width of impeller at inlet, and Vf = Velocity of flow at inlet)
Q = π.D.Vf
Q = π.b.Vf
Q = π.D.bf.V
Q = D.b.Vf
The type of centrifugal pump preferred for a specific speed of 20 r.p.m. is
Slow speed pump with radial flow at outlet
Medium speed pump with radial flow at outlet
High speed pump with radial flow at outlet
High speed pump with axial flow at outlet
Power required to drive a centrifugal pump is directly proportional to ________ of its impeller.
Diameter
Square of diameter
Cube of diameter
Fourth power of diameter
Centrifugal pump is started with its delivery valve
Kept fully closed
Kept fully open
Irrespective of any position
Kept 50% open
The Fourneyron turbine is _________ reaction turbine.
An axial flow
An inward flow
An outward flow
A mixed flow
According to fan laws, at constant pressure, the speed capacity and power vary
Directly as the air or gas density
Inversely as square root of density
Inversely as density
As square of density
For very high discharge at low pressure such as for flood control and irrigation applications, following type of pump is preferred
Centrifugal
Axial flow
Reciprocating
Mixed flow
Specific speed for reaction turbines ranges from
0 to 4.5
10 to 100
80 to 200
250 to 300
The discharge through a turbine is
Directly proportional to H1/2
Inversely proportional to H1/2
Directly proportional to H3/2
Inversely proportional to H3/2
The undershot water wheels are those in which
The wheel runs entirely by the weight of water
The wheel runs entirely by the impulse of water
The wheel runs partly by the weight of water and partly by the impulse of water
None of the above
Puck up the wrong statement about centrifugal pump
Discharge a diameter
Head a speed²
Head a diameter
Power a speed⁴
Pressure intensifier increases the pressure in proportion to
Ratio of diameters
Square of ratio of diameters
Inverse ratio of diameters
Square of inverse ratio of diameters
A hydraulic accumulator normally consists of
Two cylinders, two rams and a storage device
A cylinder and a ram
Two coaxial rams and two cylinders
A cylinder, a piston, storage tank and control valve
Slip of a reciprocating pump is defined as the
Ratio of actual discharge to the theoretical discharge
Sum of actual discharge and the theoretical discharge
Difference of theoretical discharge and the actual discharge
Product of theoretical discharge and the actual discharge
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
The cavitation in a hydraulic machine is mainly due to
Low velocity
High velocity
Low pressure
High pressure
Braking jet in an impulse turbine is used
To break the jet of water
To bring the runner to rest in a short time
To change the direction of runner
None of these
If the net positive suction head (NPSH) requirement for the pump is not satisfied, then
No flow will take place
Cavitation will be formed
Efficiency will be low
Excessive power will be consumed
The angle of taper on draft tube is
Greater than 15°
Greater than 8°
Greater than 5°
Less than 8°
The maximum number of jets generally employed in impulse turbine without jet interference is
4
6
8
12
A Francis turbine is used when the available head of water is
0 to 25 m
25 m to 250 m
Above 250 m
None of these
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
Francis, Kaplan and propeller turbines fall under the category of
Impulse turbines
Reaction turbines
Axial flow turbines
Mixed flow turbines
The force exerted by a jet of water impinging normally on a plate which due to the impact of jet, moves in the direction of jet with a velocity v is
[wa (V - v)]/2g
[wa (V - v)]/g
[wa (V - v)²]/2g
[wa (V - v²)]/g
The unit discharge through the turbine is
Q/√H
Q/H
Q/H3/2
Q/H²
Overall efficiency of a centrifugal pump is the ratio of
Energy available at the impeller to the energy supplied to the pump by the prime mover
Actual workdone by the pump to the energy supplied to the pump by the prime mover
Energy supplied to the pump to the energy available at the impeller
Manometric head to the energy supplied by the impeller per kN of water