Performance Analysis of Jet Engine of Aircraft

Abstract

The jet engine family includes the rocket jet, pulse jet, ram jet & gas turbine powered jet. The gas turbine powered jet is further broken down into the turbo jet, turbo propeller, and turbo shaft & turbofans types. These four types of engines are the most commonly used in today’s aircraft. Kiran aircraft is the basic jet trainer used in Indian air force. Kiran MkII is fitted with Orpheus engine. The engine is a straight flow turbo jet type fitted with a seven stage axial flow compressor and develops 4200+- 84 lbs/ 1909+- 38 kg static thrust at 9500 rpm at sea level. This increase to a maximum at 10,000 ft, due to the characteristics of high pressure fuel pumps in the engine fuel system. Above this height the thrust developed reduces as altitude increases. Air at atmospheric pressure is compressed adiabatically, during its passage across the compressor and diffuser, to approx 4 atm. The pressure and temperature increases and volume decreases at this stage. In the combustion chamber it is supplied at constant pressure thereby considerably increasing the volume of the air. Then during passage of the gas stream through the rear end of the combustion chamber, stationary vanes, turbine and exhaust cone, there is adiabatic expansion which is completed in the propelling nozzle with increased volume and decreased pressure at the end of the propelling nozzle, there is rejection of heat at constant pressure. The Orpheus engine which is fitted in Kiran MkII jet aircraft is performing an excellent job as it is used for giving the training to the fighter pilots.