Which device is used in thermal power plants to reduce level of pollution?
Induced draft fan
Smoke meter
Chimney
Precipitator
Correct Answer :
D. Precipitator
Related Questions
The impulse turbine rotor efficiency will have a maximum value of 0.5 cos 2α, where α is the nozzle exit flow angle, if the
Blades are equiangular
Blade velocity coefficient is unity
Blades are equiangular and frictionless
Blade solidity is 0.65
The diameter of fire tubes in Cochran boiler is of the order of
2 cm
6 cm
8 cm
12 cm
Which of the following statement is wrong?
The mechanical draught reduces the height of chimney.
The natural draught reduces the fuel consumption.
A balanced draught is a combination of induced and forced draught.
All of the above
In a nozzle, whole frictional loss is assumed to occur between
Inlet and throat
Inlet and outlet
Throat and exit
All of these
The latent heat of steam with increase of pressure
Remain same
Increases
Decreases
Behaves unpredictably
The diagram efficiency is the ratio of
Workdone on the blades to the energy supplied to the blades
Workdone on the blades per kg of steam to the total energy supplied per stage per kg of steam
Energy supplied to the blades per kg of steam to the total energy supplied per stage per kg of steam
None of the above
The function of a crosshead is to guide motion of the _________ and to prevent it from bending.
Piston rod
Connecting rod
Eccentric rod
Valve rod
A vessel into which the steam is exhausted and condensed after doing work in an engine cylinder or turbine is known as
Steam condenser
Steam boiler
Steam preheater
Economiser
The friction present between the steam and the nozzle surfaces reduces the heat drop by
10 to 15 %
15 to 25 %
25 to 40 %
40 to 60 %
100% efficiency of a thermal cycle cannot be achieved because of
Frictional losses
It is not possible to achieve 0°K temperature
Leakage
Non availability of ideal substance
In locomotive boiler, maximum steam pressure is limited to
1 kg/cm²
5 kg/cm²
10 kg/cm²
18 kg/cm²
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
The critical pressure ratio (p₂/p₁) is given by
(p₂/p₁) = [2/(n - 1)] n/(n + 1)
(p₂/p₁) = [2/(n + 1)] n/(n-1)
(p₂/p₁) = [(n - 1)/2] n + (1/n)
(p₂/p₁) = [(n + 1)/2] n - (1/n)
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
In a single acting steam engine
The steam is admitted on one side of the piston and one working stroke is produced during each revolution of the crankshaft
The steam is admitted, in turn, on both sides of the piston and one working stroke is produced during each revolution of the crankshaft
The steam is admitted on one side of the piston and two working strokes are produced during each revolution of the crankshaft
The steam is admitted, in turn, on both sides of the piston and two working strokes are produced during each revolution of the crankshaft
For water, at pressures below atmospheric;
Melting point rises slightly and boiling point drops markedly
Melting point rises markedly and boiling point drops markedly
Melting point drops slightly and boiling point drops markedly
Melting point drops slightly and boiling point drops slightly
The length of shell of a Locomotive boiler is
1 m
2 m
3 m
4 m
The shell of the Cochran boiler is made hemispherical
To give maximum space and strength
To withstand the pressure of steam inside the boiler
Both (A) and (B)
None of the above
The evaporation of 15.653 kg of water per hour from and at 100°C is called
Evaporative capacity
Factor of evaporation
Equivalent evaporation
One boiler h.p.
Thermal equilibrium means that the flow of steam is
Isothermal
Isentropic
Hyperbolic
Polytropic
The fire tubes in a Scotch marine boiler are
Horizontal
Vertical
Inclined
None of these
The rate of discharge through the nozzle __________ when the exit pressure is gradually reduced.
Remains same
Decreases
Increases
None of these
Steam engine operates on
Carnot cycle
Joule cycle
Stirling cycle
Brayton cycle
In an impulse turbine, steam expands
Wholly in blades
Wholly in nozzle
Partly in the nozzle and partly in blades
None of these
The device attached to the steam chest for preventing explosions due to excessive internal pressure of steam is called
Safety valve
Water level indicator
Pressure gauge
Fusible plug
The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is
Less
More
Equal
May be less or more depending on temperature
Natural water circulation, by convection in water tube boilers, with increase in pressure of boiler
Increases
Decreases
Remain unaffected
First increases and then decreases
Multi-stage steam turbines are of the
Velocity compounded type
Reaction type
Pressure compounded type
All 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)
Expansion ratio is the ratio of
Swept volume to the volume at cut-off
Clearance volume to the swept volume
Volume at cut-off to the swept volume
Swept volume to the clearance volume