Practice Test: Question Set - 15
1. Which of the following is a fire tube boiler?
- (A) Lancashire
boiler
- (B) Babcock
and Wilcox boiler
- (C) Yarrow
boiler
- (D) None
of these
2. In forced recirculation type boiler,
- (A) Heating takes place
at bottom and the water supplied at bottom gets converted into the mixture of
steam bubbles and hot water which rise to drum
- (B) Water is supplied in
drum and through down comers located in atmospheric condition it passes to the
water wall and rises to drum in the form of mixture of water and steam
- (C) Feed pump is employed
to supplement natural circulation in water wall type furnace
- (D) Water is converted
into steam in one pass without any recirculation
3. When the nozzle operates with the maximum mass flow, the nozzle is said to be
- (A) Choked
- (B) Under-damping
- (C) Over-damping
- (D) None
of these
4. The average value of diagram factor lies between
- (A) 0.2 to 0.5
- (B) 0.5 to 0.65
- (C) 0.65 to 0.9
- (D) 0.8 to 1.2
5. A safety valve in a locomotive starts leaking. The leaking medium will be
- (A) Water
- (B) Dry steam
- (C) Wet steam
- (D) Super heated steam
6. Which of the following statement is wrong?
- (A) The
critical pressure gives the velocity of steam at the throat equal to the
velocity of sound
- (B) The
flow in the convergent portion of the nozzle is subsonic
- (C) The
flow in the divergent portion of the nozzle is supersonic
- (D) To
increase the velocity of steam above sonic velocity (supersonic) by expanding
steam below the critical pressure, the divergent portion for the nozzle is not
necessary
7. The ratio of the energy required to produce the artificial draught (expressed in meters head or J/kg of flue gas) to the mechanical equivalent of extra heat carried away per kg of flue gases due to natural draught, is known as
- (A) Efficiency
of the boiler
- (B) Efficiency
of the chimney
- (C) Efficiency
of the fan
- (D) Power
of the boiler
8. Which device is used in thermal power plants to reduce level of pollution?
- (A) Induced draft fan
- (B) Smoke meter
- (C) Chimney
- (D) Precipitator
9. The expansion of steam, as it flows over the blades in reaction turbine, represents
- (A) Isothermal
process
- (B) Isentropic
process
- (C) Throttling
process
- (D) Free
expansion process
10. Clearance ratio is the ratio of
- (A) Clearance
volume to the swept volume
- (B) Clearance
volume to the volume at cut-off
- (C) Volume
at cut-off to the swept volume
- (D) Swept
volume to the clearance volume
11. The ultimate analysis of fuel lists
- (A) Various chemical
constituents, carbon, hydrogen, oxygen etc, plus ash as percents by volume
- (B) Various chemical
constituents, carbon, hydrogen, oxygen, etc, plus ash as percents by weight
- (C) Fuel constituents as
percents by volume of moisture, volatile, fixed carbon and ash
- (D) Fuel constituents as
percents by weight of moisture, volatile, fixed carbon and ash
12. Which of the following statement is correct?
- (A) The
expansion of steam in a nozzle follows Rankine cycle
- (B) The
friction in the nozzle increases the dryness fraction of steam
- (C) The
pressure of steam at throat is called critical pressure
- (D) All
of the above
13. The heat balance sheet for the boiler shows the
- (A) Complete
account of heat supplied by 1 kg of dry fuel and the heat consumed
- (B) Moisture
present in the fuel
- (C) Steam
formed by combustion of hydrogen per kg of fuel
- (D) All
of the above
14. A supercritical boiler is one that operates above the pressure and temperature of following values
- (A) 100 kg/cm² and 540°C
- (B) 1 kg/cm² and 100°C
- (C) 218 kg/cm² abs and 373°C
- (D) 218 kg/cm² abs and 540°C
15. Curtis turbine is a
- (A) Simple
reaction turbine
- (B) Velocity
compounded turbine
- (C) Pressure
compounded turbine
- (D) Pressure-velocity
compounded turbine