The thrust on the rotor in a centrifugal compressor is produced by________________?

Related Mcqs:

1. A centrifugal compressor works on the principle of__________________?

   A. conversion of pressure energy into kinetic energy
   B. conversion of kinetic energy into pres¬sure energy
   C. centripetal action
   D. generating pressure directly
   E. combination of A. and D.

2. Losses in a centrifugal compressor are due to__________________?

   A. inlet losses
   B. impeller channel losses
   C. diffuser losses
   D. all of the above
   E. none of the above

3. The ratio of outlet whirl velocity to blade velocity in case of centrifugal compressor is called__________________?

   A. slip factor
   B. velocity factor
   C. velocity coefficient
   D. blade effectiveness

4. Axial flow compressor has the following advantage over centrifugal compressor__________________?

   A. larger air handling ability per unit frontal area
   B. higher pressure ratio per stage
   C. aerofoil blades are used
   D. higher average velocities
   E. none of the above

5. The ratio of the increase in pressure in rotor blades to total increase in pressure in the stage is called__________________?

   A. pressure ratio
   B. pressure coefficient
   C. degree of reaction
   D. slip factor
   E. stage factor

6. An ideal air compressor cycle with clearance on p-v diagram can be represented by following processes_______________?

   A. one adiabatic, two isobaric, and one constant volume
   B. two adiabatic and two isobaric
   C. two adiabatic, one isobaric and one constant volume,
   D. one adiabatic, one isobaric and two constant volume
   E. two isobaric, two adiabatic and one constant volume

7. Volumetric efficiency of a compressor with clearance volume ________________?

   A. increases with increase in compression ratio
   B. decreases with increase in compression ratio
   C. in not dependent upon compression ratio
   D. may increase/decrease depending on compressor capacity
   E. unpredictable

8. A compressor at high altitude will draw________________?

   A. more power
   B. less power
   C. same power
   D. more/less power depending on other factors
   E. none of the above

9. The volumetirc efficiency of a compressor is calculated on the basis of __________________?

   A. volume of air inhaled at working conditions
   B. volume of air inhaled at N.T.P. conditions
   C. volume at 0°C and 1 kg/cm2
   D. volume at 20°C and 1 kg/cm2
   E. none of the above

10. In a compressor, free air delivered is the actual volume delivered at the stated pressure reduced to ____________________?

    A. N.T.P. conditions
    B. intake temperature and pressure conditions
    C. 0°C and 1 kg/cm2
    D. 20°C and 1 kg/cm2
    E. none of the above