The specific output per kg mass flow rate of a gas turbine (having fixed efficiencies of compressor and turine and fixed higher and lower temperature) with increase in pressure ratio will___________________?

Related Mcqs:

1. 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

2. The thermal efficiency of a simple gas turbine for a given turbine inlet temperature with increase in pressure ratio_____________________?

   A. increases
   B. decreases
   C. first increases and then decreases
   D. first decreases and then increases
   E. remains same

3. The pressure ratio for an open cycle gas turbine compared to closed cycle gas turbine of same h.p. is_______________?

   A. low
   B. high
   C. same
   D. low/high depending on make and type
   E. unpredictable

4. The pressure ratio of an ideal vaned compressor with increase in mass flow rate_________________?

   A. increases
   B. decreases
   C. remains constant
   D. first decreases and then increases
   E. unpredictable

5. The weight per horse power ratio for gas. turbine as compared to I.C. engine and steam turbine is________________?

   A. same
   B. higher
   C. lower
   D. uncomparable
   E. unpredictable

6. As the turbine inlet temperature increases, the thermal efficiency of gas turbine for the optimum pressure ratio_____________________?

   A. increases
   B. decreases
   C. remains same
   D. first increases and then decreases
   E. first decreases and then increases

7. The following is true for an open cycle gas turbine having exhaust heat exchanger. Atmospheric air before entering the compressor is____________________?

   A. heated
   B. compressed air before entering the combustion chamber is heated
   C. bled gas from turbine is heated and readmitted for complete expansion
   D. exhaust gases drive the compressor
   E. part of exhaust gases are heated and mixed up with atmospheric air to utilise exhaust heat

8. For a two stage compressor* if index of compression for higher stage is greater than index of compression for lower stage, then the optimum pressure as compared to ideal case will___________________?

   A. increase
   B. decrease
   C. remain unaffected
   D. other factors control it
   E. unpredictable

9. In the axial flow gas turbine, the work ratio is the ratio of____________________?

   A. compressor work and turbine work
   B. output and input
   C. actual total head tempeature drop to the isentrpic total head drop from total head inlet to static head outlet
   D. actual compressor work and theoretical comprssor work
   E. none of the above

10. If infinite number of heaters be used in a gas turbine, then expansion process in turbine approaches _________________?

    A. isothermal
    B. isentropic
    C. adiabatic
    D. isochoric
    E. isobaric