Which of the following is not a reaction turbine?
Fourneyron turbine
Journal turbine
Thomson's turbine
Pelton wheel
Correct Answer :
D. Pelton wheel
Related Questions
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 relation between hydraulic efficiency (ηh), mechanical efficiency (ηm) and overall efficiency (ηo) is
ηh = ηo × ηm
ηm = ηm × ηh
ηo = ηh × ηm
None of these
In a centrifugal pump, the regulating valve is provided on the
Casing
Delivery pipe
Suction pipe
Impeller
Any change in load is adjusted by adjusting following parameter on turbine
Net head
Absolute velocity
Blade velocity
Flow
The optimum value of vane exit angle for a centrifugal pump impeller is
10-15°
20-25°
30-40°
50-60°
In a centrifugal pump, the liquid enters the pump
At the top
At the bottom
At the canter
From sides
Low specific speed of turbine implies it is
Propeller turbine
Francis turbine
Impulse turbine
Any one of the above
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
The specific speed from 160 to 500 r.p.m. of a centrifugal pump indicates that the pump 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 axial flow at outlet
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
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
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
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
Which of the following turbine is preferred for 0 to 25 m head of water?
Pelton wheel
Kaplan turbine
Francis turbine
None of these
In axial flow fans and turbines, fluid enters and leaves as follows
Radially, axially
Axially, radially
Axially, axially
Radially, radially
The ratio of actual work available at the turbine to the energy imparted to the wheel is known as ________ efficiency.
Hydraulic
Mechanical
Overall
None of these
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 starting an axial flow pump, its delivery valve should be
Closed
Open
Depends on starting condition and flow desired
Could be either open or closed
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
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 speed 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
Manometric head, in case of a centrifugal pump, is equal to
Suction lift + Loss of head in suction pipe due to friction + Delivery lift + Loss of head in delivery pipe due to friction + Velocity head in the delivery pipe
Workdone per kN of water Losses within the impeller
Energy per kN at outlet of impeller Energy per kN at inlet of impeller
All 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 power of the wheel is
0.25 kW
0.75 kW
1.75 kW
3.75 kW
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
Geometric 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
Which of the following statement is correct?
The centrifugal pump is suitable for large discharge and smaller heads.
The centrifugal pump requires less floor area and simple foundation as compared to reciprocating pump.
The efficiency of centrifugal pump is less as compared to reciprocating pump.
All of the above
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
According to fan laws, for fans having constant wheel diameter, the air or gas capacity varies
Directly as fan speed
Square of fan speed
Cube of fan speed
Square root of fan speed
Which of the following is not an impulse turbine?
Girad turbine
Turgo turbine
Pelton wheel
Kaplan turbine
An impulse turbine is used for
Low head of water
High head of water
Medium head of water
High discharge