logo

CuriousTab

CuriousTab

Discussion


Home Mechanical Engineering Compressors, Gas Dynamics and Gas Turbines Comments

  • Question
  • Which of the following statement is correct relating to rocket engines?


  • Options
  • A. The combustion chamber in a rocket engine is directly analogous to the reservoir of a super sonic wind tunnel
  • B. The stagnation conditions exist at the combustion chamber
  • C. The exit velocities of exhaust gases are much higher than those in jet engine
  • D. all of the above

  • Correct Answer
  • all of the above 


  • Compressors, Gas Dynamics and Gas Turbines problems


    Search Results


    • 1. For maximum work, the reheating should be done to an intermediate pressure of (where p1 = Maximum pressure, and p2 = Minimum pressure)

    • Options
    • A.
    • B.
    • C.
    • D. p1p2
    • Discuss
    • 2. Free air is the air at atmospheric conditions at any specific location.

    • Options
    • A. True
    • B. False
    • Discuss
    • 3. In a centrifugal compressor, the ratio of the __________ to the blade velocity is called slip factor.

    • Options
    • A. inlet whirl velocity
    • B. outlet whirl velocity
    • C. inlet velocity of flow
    • D. outlet velocity of flow
    • Discuss
    • 4. The overall efficiency of the compressed air system is the

    • Options
    • A. ratio of shaft output of the air motor to the shaft input to the compressor
    • B. ratio of shaft input to the compressor to the shaft output of air motor
    • C. product of shaft output of air motor and shaft input to the compressor
    • D. none of the above
    • Discuss
    • 5. The temperature of air at the beginning of the compression stroke is __________ the atmospheric temperature.

    • Options
    • A. equal to
    • B. less than
    • C. more than
    • Discuss
    • 6. In a single stage, single acting reciprocating air compressor, without clearance, the workdone on the air during isentropic compression is __________ the heat required to raise the temperature of air from T1 to T2 at a constant pressure.

    • Options
    • A. equal to
    • B. less than
    • C. greater than
    • Discuss
    • 7. The pressure of air at the beginning of the compression stroke is __________ the atmospheric pressure.

    • Options
    • A. equal to
    • B. less than
    • C. more than
    • Discuss
    • 8. The process, which causes the air to enter the impeller blades of a centrifugal compressor at __________ velocity (without effecting the mass of air to flow and velocity of flow) is known as prewhirl.

    • Options
    • A. reduced
    • B. increased
    • Discuss
    • 9. The axial flow compressor is preferred in air-craft gas turbines because of

    • Options
    • A. low frontal area
    • B. higher thrust
    • C. high pressure rise
    • D. none of these
    • Discuss
    • 10. Which of the following statement is correct as regard to centrifugal compressors?

    • Options
    • A. The flow of air is parallel to the axis of the compressor.
    • B. The static pressure of air in the impeller increases in order to provide centripetal force on the air.
    • C. The impeller rotates at high speeds.
    • D. The maximum efficiency is higher than multi-stage axial flow compressors.
    • Discuss


    Comments

    There are no comments.

Enter a new Comment