The specific speed of turbine is defined as the speed of a unit
Of such a size that it delivers unit discharge at unit head
Of such a size that it delivers unit discharge at unit power
Of such a size that it requires unit power per unit head
Of such a size that it produces unit horse power with unit head
Correct Answer :
D. Of such a size that it produces unit horse power with unit head
Related Questions
Which of the following pump is successfully used for lifting water to the turbines?
Centrifugal pump
Reciprocating pump
Jet pump
Air lift pump
One horsepower is equal to
102 watts
75 watts
550 watts
735 watts
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
In an inward 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
The overall efficiency for a Pelton wheel lies between
0.50 to 0.65
0.65 to 0.75
0.75 to 0.85
0.85 to 0.90
Head developed by a centrifugal pump depends on
Impeller diameter
Speed
Fluid density
Both (A) and (B) above
According to fan laws, at constant weight of air or gas, the speed, capacity and pressure vary
Directly as the air or gas density
Inversely as square root of density
Inversely as density
As square of density
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
In a Francis turbine runner, the numbers of blades are generally between
2 to 4
4 to 8
8 to 16
16 to 24
If the ratio's of the corresponding forces acting at corresponding points are equal, then the model and the prototype are said to have.
Geometric similarity
Kinematic similarity
Dynamic similarity
None of these
The efficiency of jet propulsion for a ship with inlet orifices at right angles to the direction of motion of ship is given by
[2(Vr - v) v]/ Vr²
2(Vr + v) v]/ Vr²
[(Vr - v) v]/ Vr
[(Vr + v) v]/ Vr
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°
Medium specific speed of a pump implies it is
Centrifugal pump
Mixed flow pump
Axial flow pump
Any one of the above
The force exerted by a jet of water (in a direction normal to flow) impinging on a fixed plate inclined at an angle θ with the jet is
waV/2g × sinθ
waV/g × sinθ
waV²/2g × sin2θ
waV²/g × sinθ
For 450 m head of water, _________ shall be used.
Pelton wheel
Kaplan turbine
Francis turbine
None of these
The flow rate in gear pump
Increases with increase in pressure
Decreases with increase in pressure
More or less remains constant with increase in pressure
Unpredictable
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
The width of the bucket for a Pelton wheel is generally ________ the diameter of jet.
Double
Three times
Four times
Five times
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
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 Thomson's turbine is __________ reaction turbine.
An axial flow
An inward flow
An outward flow
A mixed flow
Which of the following pump is suitable for small discharge and high heads?
Centrifugal pump
Axial flow pump
Mixed flow pump
Reciprocating pump
Reaction turbines are used for
Low head
High head
High head and low discharge
Low head and high discharge
The optimum value of vane exit angle for a centrifugal pump impeller is
10-15°
20-25°
30-40°
50-60°
Which of the following hydraulic unit is used for transmitting increased or decreased torque to the driven shaft?
Hydraulic ram
Hydraulic intensifier
Hydraulic torque converter
Hydraulic accumulator
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
The specific speed of a hydraulic turbine depends upon
Speed and power developed
Discharge and power developed
Speed and head of water
Speed, power developed and head of water
Discharge of a centrifugal pump is (where N = Speed of the pump impeller)
Directly proportional to N
Inversely proportional to N
Directly proportional to N²
Inversely proportional to N²
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
When a piping system is made up primarily of vertical lift and very little pipe friction, the pump characteristics should be
Horizontal
Nearly horizontal
Steep
First rise and then fall