Quiznetik

Thermal Engineering 2 | Set 3

1. Why are salts deposited on the evaporator drum?

Correct : C. due to circulation of impure water

2. What is feature of the Loffler boilers?

Correct : A. evaporating water by super heated steam

3. What is the major difficulty of the La-Mont boiler?

Correct : B. deposition of salts

4. Which is the most recent economical method of power generation from boilers?

Correct : D. super critical boiler

5. Which of the following boilers has the highest heat transfer capacity?

Correct : D. supercritical boiler

6. Why boiler draught is most essential part of the thermal plants?

Correct : C. required to maintain constant air flow

7. Which is the correct formula of total draught loss?

Correct : A. ht = hv + hb + hc + hcd

8. By what is natural draught produced?

Correct : B. chimney

9. Which of the following given below as the affect on amount natural draught?

Correct : A. boiler operation

10. When is artificial draught preferred?

Correct : C. when draught produced by chimney is not sufficient

11. Artificial draught is also called as _______

Correct : D. mechanical draught

12. What is installed to transfer air into furnace in forced draught system?

Correct : A. air blower

13. Where is blower installed in induced draught system?

Correct : B. base of the chimney

14. How can exhaust gas be recovered in the induced draught?

Correct : D. by installing air preheater and economizer along the gas path

15. Which is most preferred type of draught system?

Correct : D. balanced draught

16. Which type of draught system is used in the locomotives?

Correct : D. induced steam draught system

17. Which draught system is also known as turbine draught?

Correct : A. forced steam draught

18. Which draught system is used as conjunction with chimney draught?

Correct : A. forced steam draught

19. There are two types of water feeding in a boiler, they are ________ and _________

Correct : A. open feed system and closed feed system

20. In a fire tube boiler, the water to be heated is kept in the ________

Correct : B. shell of the setup with hot gas in tubes

21. Which of the following statement is wrong?

Correct : D. all of the mentioned

22. An air preheater is installed ___________

Correct : A. between the economiser and chimney

23. What is the length of shell of a Locomotive boiler?

Correct : C. 4m

24. What is the function of a flywheel?

Correct : B. to prevent fluctuation of speed

25. The shell diameter of a Locomotive boiler is?

Correct : A. 1.5m

26. Which of the following is a water tube boiler?

Correct : C. babcock & wilcox boiler

27. The number of fire tubes in a Cochran boiler are ___________

Correct : B. 165

28. The chimney draught varies with?

Correct : D. all of the mentioned

29. The diagram factor is the ratio of ___________

Correct : D. any of the above mentioned

30. The diameter of a cylindrical shell of a Scotch marine boiler varies from ___________

Correct : C. 2.5 to 3.5m

31. Lancashire boiler has _____ internal flue tubes.

Correct : C. 2

32. Locomotive boiler is a ___________

Correct : D. multitubular, horizontal, internally fired & mobile boiler

33. The equivalent evaporation is defined as?

Correct : C. the amount of water evaporated from and at 100 degree c into dry & saturated steam

34. Non Condensing steam turbine can also be called as _________

Correct : B. back pressure steam turbine

35. Condensing turbine is used for __________

Correct : A. central power generation

36. Steam turbine is classified on basis of __________

Correct : D. all of the mentioned

37. High pressure turbine is a Non-Condensing turbine due to __________

Correct : A. exhaust conditions

38. Impulse blades are in the shape of __________

Correct : C. half moon

39. Astern turbines are used in _________

Correct : B. marine purposes

40. In condensing turbines vacuum is obtained by ____________

Correct : C. sudden drop in pressure and by removal of non condensable gases

41. Cross compound steam turbines are once used in _____________

Correct : B. marine ships

42. Where in industries do we find back-pressure turbines?

Correct : D. there is a requirement of process steam at single pressure

43. The energy conversion occurring in a steam turbine is a ______ step process.

Correct : B. 2

44. A steam turbine is basically an assemblage of ____________

Correct : C. nozzle & blades

45. A regenerative steam cycle renders ____________

Correct : D. decreased work output per unit mass of steam as well as increased thermal efficiency

46. The reheat factor is the ratio of the ____________

Correct : B. cumulative heat drop to the isentropic heat drop

47. Thermal equilibrium means that the flow of steam is ____________

Correct : C. isentropic

48. Multi-stage steam turbines are of the ___________

Correct : D. all of the mentioned

49. The impulse reaction turbine has its driving force ___________

Correct : A. partly as an impulsive force and partly as a reaction force

50. In a nozzle, whole frictional loss is assumed to occur between ___________

Correct : B. throat and exit

51. The ratio of total useful heat drop to the total isentropic heat drop is called?

Correct : C. internal efficiency

52. What is the action of steam in a steam turbine?

Correct : B. dynamic

53. The critical pressure gives the velocity of steam at the throat ___________

Correct : A. equal to the velocity of sound

54. The flow through a nozzle is regarded as ___________

Correct : D. isentropic flow

55. The steam leaves the nozzle at a ____________

Correct : A. low pressure and a high velocity

56. De-Laval turbine is a ____________

Correct : C. single rotor impulse turbine

57. The Parsons’ reaction turbine has ____________

Correct : D. identical fixed and moving blades

58. The ratio of the useful heat drop to the isentropic heat drop is called ____________

Correct : B. nozzle efficiency

59. Rateau turbine is ____________

Correct : D. pressure compounded turbine

60. The value of the reheat factor varies from ____________

Correct : D. 1.02 to 1.06

61. In reaction turbines, the axial thrust is due to ____________

Correct : C. both pressure drop across the rotor and change in axial velocity

62. The flow of steam is super-sonic ____________

Correct : D. in the divergent portion of the nozzle

63. The variation of steam pressure in the nozzle depends upon ____________

Correct : D. all of the mentioned

64. A binary vapour plant consists of ____________

Correct : D. all of the mentioned

65. The steam enters the nozzle at a ____________

Correct : D. high pressure and a high velocity

66. In a reaction turbine, when steam flows through the fixed blades ____________

Correct : A. pressure decreases while velocity increases

67. Steam turbines are used for ____________

Correct : D. all of the mentioned

68. Curtis turbine is a ____________

Correct : D. pressure-velocity compounded turbine

69. Which of the following statement is correct?

Correct : D. all of the mentioned

70. What is the purpose of governing in steam turbines?

Correct : B. maintain the speed of the turbine

71. The ratio of the isentropic heat drop to the heat supplied is called ____________

Correct : D. rankine efficiency

72. The reheat factor depends upon ____________

Correct : D. all of the mentioned

73. What is the critical pressure ratio for initially dry saturated steam?

Correct : B. 0.577

74. In an impulse turbine, steam expands ____________

Correct : A. wholly in nozzle

75. A steam nozzle converts ____________

Correct : C. heat energy of steam into kinetic energy

76. If the critical pressure ratio for steam is 0.546, then the steam is initially ____________

Correct : C. superheated

77. A stage, in reaction turbine, is represented by ____________

Correct : A. each row of blades

78. Steam turbines may be classified according to ____________

Correct : D. all of the mentioned

79. A steam nozzle converts ____________

Correct : A. heat energy of steam into kinetic energy

80. A steam turbine with no nozzle is?

Correct : A. reaction turbine

81. _______ of electricity in United States is produced using steam turbine.

Correct : A. 88%

82. When steam pressure ________ it becomes superficial fluid.

Correct : B. increases

83. Steam turbines used in nuclear reactors use __________

Correct : A. superficial fluids

84. Superficial steam power plants operate at _____ temperatures.

Correct : A. high

85. Energy efficiency of superficial steam is _________

Correct : B. high

86. Superficial steam turbines can be operated at ________

Correct : C. high speeds

87. Superficial steam turbines releases _______ CO2.

Correct : A. high

88. Which statement about reaction turbine is false?

Correct : D. steam continuously losses its heat as flows over the rotor blades

89. Reaction turbines are characterized by ___________

Correct : C. relatively low rpm and steam expension over rotor blades

90. In condensing turbine what is the back pressure of the turbine?

Correct : D. below atmospheric pressure

91. Having two separate units for process heat and power is?

Correct : B. useless

92. Back pressure turbine is placed between ____________

Correct : D. boiler & turbine

93. Addition of an infinitesimal amount of heat at the highest temperature is because ___________

Correct : C. to initiate superheating

94. High moisture content is involved during expansion of steam because ___________

Correct : C. to obtain a higher temperature of heat addition

95. What is the relation of the mean temperature of heat addition and cycle efficiency?

Correct : B. both are directly proportional

96. Temperature of heat rejection in a condenser can be lowered by using?

Correct : C. refrigerant

97. The use of which of the following becomes necessary during expansion of steam?

Correct : A. reheat

98. What is the specific heat of the ideal working fluid used in vapour power cycle?

Correct : C. should be small

99. What is the importance of the freezing point of the working fluid in the vapour power cycle?

Correct : A. freezing point of working fluid should be below the room temperature

100. The engines which are operating on gas power cycle are?

Correct : C. either cyclic or non-cyclic