In the aircraft propellers __________________? A. the propulsive matter is caused to flow around the propelled body B. propulsive matter is ejected from within the propelled body C. its functioning does not depend on presence of airD. all of the…
Work ratio of a gas turbine may be improved by f____________________? A. decreasing the compression work B. increasing the compression work C. increasing the turbine work D. decreasing the turbine workE. A. and C. above
Reheating in gas turbine results in___________________? A. increase of work ratio B. decrease of thermal efficiency C. decrease of work ratioD. both A. and B. above E. both B. and C. above
In which case the air-fuel ratio is likely to be maximum _________________? A. 2-stroke engine B. 4-stroke petrol engine C. 4-stroke diesef engine D. multi-cylinder engineE. gas turbine
High air-fuel ratio is used in gas turbines______________________? A. to increase the output B. to increase the efficiency C. to save fuelD. to reduce the exit temperature E. none of the above
In jet engines the compression ratio__________________? A. varies as square root of the speed B. Varies linearly to the speedC. varies as square of the speed D. varies as cube of the speed E. is constant irrespective of variation in…
Air-fuel ratio in a jet engine will be of the order of__________________? A. 10: 1 B. 15: 1 C. 20 : 1D. 60 : 1 E. 100 :
The effective power of gas turbines is increased by adding the following in compressor__________________? A. ammonia and water vapour B. carbon dioxide C. nitrogen D. hydrogen E. none of the above
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___________________? A. increase first at fast rate and then slow…
The following property is most important for material used for gas turbine blade___________________? A. toughness B. fatigueC. creep D. corrosion resistance E. bulk modulus