Anna University-Automotive Engines-Question bank

 AUTOMOTIVE  ENGINES

QUESTIONS FROM UNIVERSITY EXAM

Semester: III                                                                          Max. Marks: 100

PART – A                                                                              (10 x 2 = 20 marks)

1. What is the use of air standard cycle?
2. Draw the Otto cycle on P-V diagram
3. what are the firing order used in 4 and 6 cylinder engines
4. what is stiochiometric air fuel ratio
5. what are the three basic types of carburetors
6. what are the different methods of engine cooling
7. what is blow by
8. what is flame front
9. what are the various types of combustion chambers used in SI engines
10. what is scvangening efficiency
11. what is short circuiting
12. what is carnot cycle  and its importance
13. What are different air fuel mixtures on which an engine can operate
14. Write down the firing order for four and six cylinder engines
15. what is indicator diagram
16. what is the necessity of firing order in a multicylinder engines
17. what are the mixture limits for inflammability
18. what is the difference between a constant choke carburetor and a constant vacuum carburetor
19. what is a thermostat
20. what is the need for providing crankcase ventilation
21. what are the variable s that affect the knock of SI engines
22. How is the location of the spark plug can influence knocking tendency
23. why scavenging is important in two stroke engines compared to four stroke engines
24. Define trapping efficiency
25. List the different types of ignition system used in vehicles 
26. What is the use of condenser in ignition system
27. What are the main functions of air injection pump?
28. What is meant by crank case ventilation?
29. Write the reason for cooling an engine
30. what is the advantage of air cooling system
31. what is meant by abnormal combustion
32. What is delay period and what are the factors that affect the delay period?
33. Define enthalpy
34. Write down the components of ignition system used in automobiles
35. Write down the possible faults in conventional ignition system

36. Draw the diagram for an ignition coil and name the components
37. Write any four advantage of  4 stroke petrol engine over 2 stroke petrol engine
38. write the air standard efficiency of an Otto cycle
39.  write ant four factor that affects the process of combustion
40. what are the various requirement of good carburetor
41. what is the main function of an spark plug
42. write different methods of SI lubricating system
43. write the reason for cooling an engine
44. what is meant by abnormal combustion
45. What is a homogeneous and heterogeneous mixture?
46. what is opposed piston engine
47. Define dwell angle and mention its importance
48. Briefly explain about two types of spark plug used in automobiles
49. List the advantage of Electronic ignition system with conventional type
50. Write down the firing order for four and six cylinder engines
51. List the different types of ignition system used in vehicles 
52. What is the use of condenser in ignition system
53. Write down the components of ignition system used in automobiles
54. Write down the possible faults in conventional ignition system

                                            

PART – B                                                                                    (16 x 2 = 32 marks)

55. Compare four stroke and two stroke cycle engines and bring out their relative merits and demerits
56. Describe with suitables sketches the idling system and accelerating pump of a modern carburetor
57. sketch a mechanical fuel pump and describe its working
58. Explain with a neat sketch the forced circulation cooling system
59. Discuss the different properties of lubricants
60. Discuss the design criteria for a S.I engine combustion chamber
61. Explain with neat sketches the two different types of two stroke engines
62. Explain the various scavenging pumps used in a two stroke engines
63. Discuss the two stroke engine construction and operation with neat sketches
64. with a neat sketch explain the working principles of a simple carburetor
65. Explain briefly the electronic fuel injection system used in some modern cars
66. Explain with neat sketches the thermosypon cooling system and pressure cooling system
67. Discuss the various types of combustion chambers used in SI engines
68. Explain with a graph the three possible theoretical scvangening processes
69. Explain with neat sketch the cross flow scvangening and uniflow scvangening 
70. Briefly explain the principle of four stroke petrol engine with a simple sketch
71. Draw the ideal and actual indicator diagram for a four stroke petrol engine and explain why they differ each other.
72. Draw the sketch of a downdraught carburetor. How do the idle and low speed circuits work in this carburetor

73. Briefly explain the working principle of line fuel injection pump
74. Explain the dry sump lubricating system with neat sketch
75. What is an air cooling system and in which type of engine it is normally used.
76. Explain the desirable properties of a good lubricant
77. What are the various types of combustion chamber used in SI engines? explain them briefly
78. Write any one type of scavenging pump used in a 2 stroke petrol engine and explain briefly.
79. Define the following

i)                    Delivery ratio

ii)                  Trapping efficiency

iii)                Relative cylinder charge

iv)                Scavenging efficiency

80. A gas working on the Otto cycle has a cylinder of diameter 200 mm and stroke 250 m. The clearance volume is 1570 CC. Find the air standard efficiency. Assue Cp= 1.004 KJ/kg K and Cv = 0.7171 KJ/kg K for air.
81. With a suitable sketches explain the various modern automobiles carburetors
82. Give brief account of the injection in SI engine
83. Clearly explain the various Wet sump lubricating system. Compare wet sump and dry sump lubrication
84. With suitable sketches explain the liquid cooling system of an Automobile.
85. Explain the phenomenon of knock in SI engine and compare with it with CI engines
86. Explain various scavenging pumps used in a two stroke engines
87. what are the advantage and disadvantage of 2 stroke engine
88. Explain with figures various types of combustion chambers used in SI engines.
89. With the aid of a circuit diagram explain the working principles of a battery coil ignition system.
90. Describe the working principles of a centrifugal spark advance mechanism with 

       neat diagram

91. Describe the necessity of the spark advance mechanism in an engine
92. With the aid of a diagram describe  vacuum spark advance mechanism
93. Draw the diagram for an ignition coil and name the components
94. With the aid of a circuit diagram explain the working principles of a battery coil ignition system.
95. Describe the working principles of a centrifugal spark advance mechanism with 

       neat diagram

97. Describe the necessity of the spark advance mechanism in an engine

98. With the aid of a diagram describe vacuum spark advance mechanism