1. Within the boiler, the steam has highest temperature in
(b) water tubes.
(a) super-heater
(c) water walls.
(d) water drum.
Answer: (a) super-heater
2. Which of the following enters the superheater ?
(a) Superheated steam.
(b) Wet steam.
(c) Hot water.
(d) Cold water.
Answer: (b) Wet steam.
3. Superheated steam is always
(a) at a pressure more than that of the boiler steam.
(b) at a pressure lower than the maximum cycle pressure.
(c) at a temperature higher than the temperature of saturation corresponding to the steam pressure.
(d) none of the above.
Answer: (b) at a pressure lower than the maximum cycle pressure.
4. Steam is superheated in order to
(a) improve Rankine cycle efficiency.
(b) reduce initial condensation losses.
(c) avoid too high temperature in the last stage of the turbine.
(d) all of the above.
Answer: (d) all of the above.
5. The function of the economizer is to
(a) heat up the incoming water with exhaust steam.
(b) heat up the pulverized fuel by exhaust gases.
(c) heat up the incoming air by exhaust gases.
(d) heat up the incoming water by exhaust gases.
Answer: (d) heat up the incoming water by exhaust gases.
6. The main function of economizer of a boiler plant is to
(a) increase steam production.
(b) reduce fuel consumption.
(c) increase steam pressure.
(d) increase life of the boiler.
Answer: (b) reduce fuel consumption.
6. In a steam power plant heat from the flue gases is recovered in
(a) a condenser.
(b) a chimney.
(c) economizer and air preheated.
(d) a de-super-heater.
Answer: (c) economizer and air preheated.
7. Economizer in a steam power plant
(a) improves the boiler efficiency by 10-12%.
(b) saves fuel consumption by 5-15%.
(c) becomes a necessity for pressure exceeding 70 kg/cm2.
(d) all of the above.
Answer: (d) all of the above.
8. The advantage of reheating of steam in a turbine is that
(a) it increases the efficiency of the turbine.
(b) it reduces the wears on the blades.
(c) it increases the work-done through the turbine.
(d) all of the above advantages.
Answer: (d) all of the above advantages.
9. Air pre-heater in a steam power plant
(a) recovers the heat from the flue gases leaving the economizer.
(b) improves combustion rate.
(c) raises the temperature of the furnace gases.
(d) all of the above.
Answer: (d) all of the above.
10. Condensers in thermal power plants are for condensing
(a) steam to water.
(b) water to ice.
(c) hydrogen gas to liquid gas.
(d) carbon dioxide to dry ice.
Answer: (a) steam to water.
11. A condenser in a steam power plant condenses steam coming out of
(a) turbine.
(b) boiler.
(c) economizer.
(d) super-heater.
Answer: (a) turbine.
12. In a steam power plant water is used for cooling purposes in
(a) economizer.
(b) condenser.
(c) super-heater.
(d) electrostatic precipitator.
Answer: (b) condenser.
13. In a steam turbine cycle, the lowest pressure occurs in
(a) condenser.
(b) turbine inlet.
(c) boiler.
(d) super-heater.
Answer: (a) condenser.
14. Increase in condenser back pressure will lead to a
(a) loss.
(b) gain.
(c) none of these.
Answer: (a) loss.
15. In which part of the thermal power plant, the steam pressure is less than that of atmosphere ?
(a) Boiler.
(b) Turbine.
(c) Super-heater.
(d) Condenser.
Answer: (d) Condenser.
16. The major function of the condenser is to
(a) remove the condensate for boiler feed water.
(b) condense steam.
(c) reduce the back pressure so that maximum heat energy can be extracted from steam.
(d) provide a closed cycle.
Answer: (c) reduce the back pressure so that maximum heat energy can be extracted from steam.
17. The function of a condenser in a steam power plant is to
(a) condense the large volume of steam to water to be used as boiler feed water.
(b) receive the large volume of steam exhausted from the steam turbine.
(c) maintain pressure below atmospheric so that maximum heat energy can be extracted from steam.
(d) all of the above.
Answer: (d) all of the above.
18. Evaporative type of condenser has
(a) steam in pipes surrounded by water.
(b) water in pipes surrounded by steam outside.
(c) steam and cooling water mixed to give condensate.
(d) none of the above.
Answer: (a) steam in pipes surrounded by water.
19. In a jet type condenser
(a) steam passes through tubes and cooling water surrounds them.
(b) water passes through tubes and steam surrounds them.
(c) steam and cooling water mix.
(d) none of the above.
Answer: (c) steam and cooling water mix.
20. In a shell and tube surface condenser
(a) steam passes through the tubes and cooling water surrounds them. (b) cooling water passes through the tubes and steam surrounds them. (c) steam and water mix to give condensate.
(d) none of the above.
Answer: (b) cooling water passes through the tubes and steam surrounds them.