In a 50% reaction turbine stage, tangential component of absolute velocity at rotor inlet is 537 m/s and the blade velocity is 454 m/s. The power output in kW of steam will be
260 kW
282 kW
296 kW
302 kW
Correct Answer :
B. 282 kW
Related Questions
In case of non-condensing steam engines, the pressure of steam in the cylinder during exhaust stroke is _________ the condenser pressure.
Equal to
Lower than
Higher than
None of these
The numbers of fire tubes in a Cochran boiler are
75
115
165
225
With increase in load, radiant superheater has
Drooping characteristic
Linear characteristic
Rising characteristic
Flat characteristic
The feed check valve is used in order to
Regulate flow of boiler water
Check level of water in boiler drum
Recirculate unwanted feed water
Allow high pressure feed water to flow to drum and not allow reverse flow to take place
In a reaction turbine when the degree of reaction is zero, then there is
No heat drop in moving blades
No heat drop in fixed blades
Maximum heat drop in moving blades
Maximum heat drop in fixed blades
A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180° to each other, is called
Receiver type compound engine
Tandem type compound engine
Woolf type compound engine
Both (A) and (B)
The ratio of the volume at cut-off to the swept volume is called
Cut-off ratio
Expansion ratio
Clearance ratio
None of these
Degree of reaction is defined as the ratio of
Heat drop in fixed blades to the heat drop in moving blades
Heat drop in moving blades to the heat drop in fixed blades
Heat drop in moving blades to the heat drop in fixed blades plus heat drop in moving blades
Heat drop in fixed blades plus heat drop in moving blades to the heat drop in moving blades
The fire tubes in a Cochran boiler usually have _________ diameter.
6.25 mm
62.5 mm
72.5 mm
92.5 mm
A compound steam engine in which the high pressure and low pressure cylinders have common piston rod, is called
Receiver type compound engine
Tandem type compound engine
Woolf type compound engine
None of these
The draught may be produced by a
Mechanical fan
Chimney
A steam jet
All of these
Maximum energy loss in a boiler occurs due to
Unburnt carbon in ash
Incomplete combustion
Ash content
Flue gases
In locomotives, the draught is produced by
Chimney
Induced draft fan
Both combined (A) and (B)
Steam jet draught
In a Tandem type compound engine, the high pressure and low pressure cylinders
Have common piston rod
Are set at 90°
Have separate piston rods
Are set in V-arrangement
The reheat factor depends upon
Initial pressure and superheat
Exit pressure
Turbine stage efficiency
All of these
The relative efficiency is defined as the
Ratio of thermal efficiency to Rankine efficiency
Ratio of brake power to the indicated power
Ratio of heat equivalent to indicated power to the energy supplied in steam
Product of thermal efficiency and Rankine efficiency
The length of shell of a Locomotive boiler is
1 m
2 m
3 m
4 m
Which of the following statement is correct?
The expansion of steam in a nozzle follows Rankine cycle.
The friction in the nozzle increases the dryness fraction of steam.
The pressure of steam at throat is called critical pressure.
All of the above
The clearance in the engine cylinder
Increases the mean effective pressure
Increases the workdone
Decreases the efficiency of the engine
All of these
Bomb calorimeter is used to determine
Higher calorific value at constant volume
Lower calorific value at constant volume
Higher calorific value at constant pressure
Lower calorific value at constant pressure
In order to reduce the rotor speed of an impulse turbine, the method employed is
Velocity compounding
Pressure compounding
Pressure-velocity compounding
All of these
The object of producing draught in a boiler is
To provide an adequate supply of air for the fuel combustion
To exhaust the gases of combustion from the combustion chamber
To discharge the gases of combustion to the atmosphere through the chimney
All of the above
The critical pressure gives the velocity of steam at the throat
Equal to the velocity of sound
Less than the velocity of sound
More than the velocity of sound
None of these
A compound steam engine in which piston rods of high pressure and low pressure cylinders are attached to two different cranks set at 90° to each other, is called
Receiver type compound engine
Tandem type compound engine
Woolf type compound engine
Both (A) and (B)
Carbonisation of coal is the process of
Pulverising coal in inert atmosphere
Heating wood in a limited supply of air at temperatures below 300°C
Strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel
Binding the pulverised coal into briquettes
The cylinder dimensions of a compound engine may be designed on the basis of
Equal power developed in each cylinder for uniform turning moment
Equal initial piston loads on all pistons for obtaining same size of piston rod, connecting rod etc. for all cylinders
Equal temperature drop in each cylinder for economy of steam
All of the above
An ideal regenerative cycle is
Equal to Carnot cycle
Less than Carnot cycle
More than Carnot cycle
Could be anything
Natural water circulation, by convection in water tube boilers, with increase in pressure of boiler
Increases
Decreases
Remain unaffected
First increases and then decreases
The maximum steam pressure in a Locomotive boiler is limited to
0.18 MN/m²
1.8 MN/m²
18 MN/m²
180 MN/m²
For a Parson's reaction turbine, if α₁ and α₂ are fixed blade angles at inlet and exit respectively and β₁ and β₂ are the moving blade angles at entrance and exit respectively, then
α₁ = α₂ and β₁ = β₂
α₁ = β₁ and α₂= β₂
α₁ < β₁ and α₂ > β₂
α₁ = β₂ and β₁ = α₂