| 1. | The temperature of air at the beginning of the compression stroke is ......... the atmospheric temperature ? | |
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equal to
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less than
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more than
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none
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Report Question| 2. | A compressor mostly used for supercharging of I.C. engines is ? | |
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radial flow compressor
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axial flow compressor
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roots blower
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reciprocating compressor
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| 3. | The multi-stage compression of air as compared to single stage compression ? | |
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improves volumetric efficiency for the given pressure ratio
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reduces workdone per kg of air
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gives more uniform torque
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all of these
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| 4. | In a four stage compressor, if the pressure at the first and third stage are 1 bar and 16 bar, the the delivery pressure at the fourth stage will be ? | |
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1 bar
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16 bar
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64 bar
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256 bar
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| 5. | Which of the following statement is correct relating to rocket engines ? | |
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The combustion chamber in a rocket engine is directly analogous to the reservoir of a super sonic wind tunnel
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The stagnation conditions exist at the combustion chamber
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The exit velocities of exhaust gases are much higher than those in jet engine
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all of the above
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| 6. | Reheating in a gas turbine ? | |
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increases the thermal efficiency
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increases the compressor work
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increases the turbine work
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decreases the thermal efficiency
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| 7. | In a centrifugal compressor, the highest Mach number leading to shock wave in the fluid flow occurs at ? | |
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diffuser inlet radius
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diffuser outlet radius
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impeller inlet radius
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impeller outlet radius
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| 8. | The volumetric efficiency of a compressor ? | |
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increases with decrease in compression ratio
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decreases with decrease in compression ratio
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increases with increase in compression ratio
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decreases with increase in compression ratio
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| 9. | The maximum delivery pressure in a rotary air compressor is ? | |
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10 bar
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20 bar
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30 bar
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50 bar
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| 10. | Which one of the following is the effect of blade shape on performance of a centrifugal compressor ? | |
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Backward curved blades has poor efficiency
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Backward curved blades lead to stable performance
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Forward curved blades has higher efficiency
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Forward curved blades produce lower pressure ratio
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