During base load operation, the best method of controlling compressor is ___________________?

Related Mcqs:

1. During peak load periods, the best method of controlling compressors is___________________?

   A. start-stop motor
   B. constant speed unloader
   C. relief valve
   D. variable speed
   E. none of the above

2. The vloumetric efficiency of compressor with increase in compression ratio will ___________________?

   A. increase
   B. decrease
   C. remain same
   D. may increase/decrease depending on clearance volume
   E. none of the above

3. The compressor capacity with decrease in suction temperature_________________?

   A. increases
   B. decreases
   C. remains unaffected
   D. may increase or decrease depending on compressor capacity
   E. increases upto certain limit and then decreases

4. The net work input required for compressor with increase in clearance volume_____________________?

   A. increases
   B. decreases
   C. remains same
   D. increases/decreases depending on com-pressor capacity
   E. unpredictable

5. The clearance volume of the air compressor is kept minimum because____________________?

   A. it allows maximum compression to be achieved
   B. it greatly affects volumetric efficiency
   C. it results in minimum work
   D. it permits isothermal compression
   E. none of the above

6. In multistage compressor, the isothermal compression is achieved by_________________?

   A. employing intercooler
   B. by constantly cooling the cylinder
   C. by running compressor at very slow speed
   D. by insulating the cylinder
   E. none of the above

7. 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.

8. For supplying intermittent small quantity of air at high pressure, following compressor is best suited__________________?

   A. centrifugal
   B. reciprocating
   C. axial
   D. screw
   E. turbo jet

9. The thermodynamic efficiency of rotary compressor is based on_______________?

   A. isothermal compression
   B. adiabatic compression
   C. isentropic compression
   D. polytropic compression
   E. none of the above

10. 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