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

Related Mcqs:

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

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

2. Clearance volume in actual reciprocating compressors is essential __________________?

   A. to accommedate Valves in the cylinder head
   B. to provide cushioning effect
   C. to attain high volumetric efficiency
   D. to avoid mechanical bang of piston with cylinder head
   E. to provide cushioning effect and also to avoid mechanical bang of piston with cylinder head

3. Volumetric efficiency of air compressors is of the order of________________?

   A. 20-30%
   B. 40-50%
   C. 60-70%
   D. 70-90%
   E. 90-100%

4. Rotary compressors are suitable for ____________________?

   A. large discharge at high pressure
   B. low discharge at high pressure
   C. large discharge at low pressure
   D. low discharge at low pressure
   E. there is no such limitation

5. Maximum temprature in a gas turbine is of the order of COMPRESSORS, GAS TURBINES AND JET ENGINES______________________?

   A. 2500°C
   B. 2000°C
   C. 1500°C
   D. 1000°C
   E. 700°C

6. There is a certain pressure ratio (optimum) for a gas turbine at which its thermal efficiency is maximum. With increase in turbine temperature, the value of pressure ratio for the peak efficiency would__________________?

   A. remain same
   B. decrease
   C. increase
   D. unpredictable
   E. none of the above

7. The capacity of compressor will be highest when its intake temperature is___________________?

   A. lowest
   B. highest
   C. anything.
   D. atmospheric
   E. none of the above

8. The indicated work per unit mass of air delivered is___________________?

   A. directly proportional to clearance volume
   B. greatly affected by clearance volume
   C. not affected by clearance volume
   D. inversely proportional to clearance volume

9. Actual compression curve is___________________?

   A. same as isothermal
   B. same as adiabatic
   C. better than isothermal and adiabatic
   D. in between isothermal and adiabatic
   E. none of the above

10. The working fluid in ai turbine is___________________?

    A. in two phases
    B. in three phases
    C. in a single phase
    D. in the form of air and water mixture
    E. gas and no air