Compression efficiency is compared against_____________________?

Related Mcqs:

1. Isothermal compression efficiency, even when running at high speed, can be approached by using A. multi-stage compression B. cold water spray C. both A. and B. above D. fully insulating the cylinder E. high stroke_________________?

   Isothermal compression efficiency, even when running at high speed, can be approached by using
   A. multi-stage compression
   B. cold water spray
   C. both A. and B. above
   D. fully insulating the cylinder
   E. high stroke

2. 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

3. The advantage of multistage compression over single stage compression is ________________?

   A. lower power consumption per unit of air delivered
   B. higher volumetric efficiency
   C. decreased discharge temperature
   D. moisture free air
   E. all of the above

4. For minimum work in multistage compression, assuming same index of compression in all stages_________________?

   A. work done in first stage should be more
   B. work done in subsequent stages should increase
   C. work done in subsequent stages should decrease
   D. work done in all stages should be equal
   E. work done in any stage is no criterion for minimum work but depends on other factors

5. 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

6. The thermal efficiency of a semi-diesel cycle having fixed compression ratio and fixed quantity of heat, with increase in pressure ratio will_______________?

   A. increase
   B. decrease
   C. remain unaffected
   D. increase/decrease depending upon engine capacity
   E. first increase and then decrease

7. The efficiency of the ideal diesel cycle is ________ than that of Otto cycle, for the same compression ratio

   A. Higher
   B. Lower
   C. Equal
   D. None of these

   Submitted by: Faheem Zaman Dhaunroo

8. Temperature of gases at end of compression as compared to exhaust gases in a gas turbine is_________________?

   A. higher
   B. lower
   C. equal
   D. can’t be compared
   E. unpredictable

9. 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

10. The thermal efficiency of a petrol engine of two stroke with crank case scavenging as compared to four stroke petrol engine with same comperssion ratio will be_____________________?

    A. higher
    B. lower
    C. same
    D. depends on size of engine
    E. unpredictable.