TSEE MCQ part 3

1. The measured O2 in flue gas is 5.5 % by volume, the excess air percentage will be

a) 41 % b) 55.9 %

c) 35.5 % d) None of the above

Answer C

 

2. The efficiency of a reheating furnace, operating at 10 tonnes per hour consuming furnace oil of 230 kg/hour for reheating the material from 40 °C to 1100 °C (consider specific heat of material is 0.13 kCal / kg °C and calorific value of furnace oil is 10,000 kCal/kg) is _______.

a) 60 % b) 70 % c) 80 % d) None of the above

Answer A

 

3. In FBC boiler the combustion is carried out at a temperature

a) Closer to saturated steam temperature

b) Below ash fusion temperature of fuel used

c) At adiabatic combustion temperature of fuel

d) At and above ash fusion temperature of fuel

Answer B

 

5. Turbine cylinder efficiency is given as a ratio of________________________

a) Actual enthalpy drop and isentropic enthalpy drop

b) Useful heat and power output

c) Useful power and heat output

d) All of the above

Answer A

 

6. The effectiveness of a heat exchanger depends on

a) Specific heat of hot fluid b) Specific heat of cold fluid

c) Inlet temperature of hot fluid d) LMTD.

Answer D

 

7. The evaporation ratio of a coal-fired boiler is 4. Steam enthalpy is 640 kCal/kg; feed water temperature is 55 0C, Calorific Value of coal is 4000 kCal/kg. The boiler efficiency is ________

a) 49 % b) 82 %

c) 58.5 % d) 70 %

Answer C

 

9. Removal of dissolved gases from the boiler feed water is called

a) Degasification b) Deaeration c) Deoxidation d) None of the above

Answer B

 

10. Which one of the following is a high temperature heat recovery device?

a) Regenerator b) Heat pump c) Heat wheel d) Heat pipe

Answer A

 

11. In reheating furnace, scale losses will

a) Increase with excess air b) Decrease with the excess air

c) Have no relation with excess air d) Increase with CO2% in flue gas

Answer A

 

12. Transfer of heat without a conveying medium is possible with

a) Conduction b) Radiation

c) Convection d) None of the above

Answer B

 

13. Which of the following increases, when high pressure steam is discharged to atmosphere?

a) Sensible heat b) Total enthalpy of steam

c) Saturation temperature d) Specific volume

Answer D

 

14. Removal of condensate from main steam line is done to prevent

a) Steam locking b) Air locking

c) Water hammer d) All of the above

Answer C

 

15. For flash steam calculation, flash steam quantity available depends upon

a) Condensate pressure and flash steam pressure

b) Steam pressure

c) Steam enthalpy at atmospheric pressure

d) Total heat of flash steam

Answer A