Home / Mechanical Engineering / Compressors, Gas Turbines and Jet Engines :: section-1

Mechanical Engineering :: Compressors, Gas Turbines and Jet Engines

  1. Stalling of blades in axial flow compressor is the phenomenon of

  2. A.

     Air stream blocking the passage

    B.

     Motion of air at sonic velocity

    C.

     Unsteady periodic and reversed flow

    D.

     Air stream not able to follow the blade contour


  3. A rocket engine uses __________ for the combustion of its fuel.

  4. A.

     Surrounding air

    B.

     Compressed atmospheric air

    C.

     Its own oxygen

    D.

     None of these


  5. Separators in compressor installations are located

  6. A.

     Before inter-cooler

    B.

     After inter-cooler

    C.

     After receiver

    D.

     Between after-cooler and air receiver


  7. Mechanical efficiency of gas turbines as compared to I.C engines is

  8. A.

     Higher

    B.

     Lower

    C.

     Same

    D.

     None of the above


  9. The maximum combustion pressure in gas turbine as compared to I.C. engine is

  10. A.

     More

    B.

     Less

    C.

     Same

    D.

     Depends on other factors


  11. Which of the following fuels can be used in turbojet engines?

  12. A.

     Liquid hydrogen

    B.

     High speed diesel oil

    C.

     Kerosene

    D.

     Methyl alcohol


  13. Ram compression in turbojet involves

  14. A.

     Reduction of speed of incoming air and conversion of part of it into pressure energy

    B.

     Compression of inlet air

    C.

     Increasing speed of incoming air

    D.

     Lost work


  15. Standard air is the air at ________ and relative humidity of 36 percent.

  16. A.

     0.1 bar and 20°C

    B.

     1 bar and 20°C

    C.

     0.1 bar and 40°C

    D.

     1 bar and 40°C


  17. Which of the following statement is correct as regard to centrifugal compressors?

  18. 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 multistage axial flow compressors


  19. To avoid moisture troubles, the branch connections from compressed air lines should be taken from

  20. A.

     Top side of main

    B.

     Bottom side of main

    C.

     Left side of main

    D.

     Right side of main