An aircraft flies at Mach 1.5 at 510o00 ft (Pa=11.0KPa,Ta=216.7 K) propelled by a simple turbojet...

 

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An aircraft flies at Mach 1.5 at 510o00 ft (Pa=11.0KPa,Ta=216.7 K) propelled by a simple turbojet engine. The air enters the compressor and turbine at a rate of 20kg/s. (y=1.4,cp=1005J/(kg•K)). a. Find the stagnation temperature and pressure into the compressor, if the inlet is effectively isentropic. b. The engine compressor has a pressure ratio of 15 with an isentropic efficiency of 85%. Find the compressor work input. c. In the combustor the velocities are low (so the stagnation and static pressure are equal) with 5% pressure drop. At turbine entry the stagnation temperature is 1400 K and the turbine has an efficiency of 89% and 65% work output from turbine is used as compressor work input. Calculate the pressure ratio of the turbine and the thermal efficiency. d. If the final propelling nozzle is isentropic, find the velocity of the jet. An aircraft flies at Mach 1.5 at 510o00 ft (Pa=11.0KPa,Ta=216.7 K) propelled by a simple turbojet engine. The air enters the compressor and turbine at a rate of 20kg/s. (y=1.4,cp=1005J/(kg•K)). a. Find the stagnation temperature and pressure into the compressor, if the inlet is effectively isentropic. b. The engine compressor has a pressure ratio of 15 with an isentropic efficiency of 85%. Find the compressor work input. c. In the combustor the velocities are low (so the stagnation and static pressure are equal) with 5% pressure drop. At turbine entry the stagnation temperature is 1400 K and the turbine has an efficiency of 89% and 65% work output from turbine is used as compressor work input. Calculate the pressure ratio of the turbine and the thermal efficiency. d. If the final propelling nozzle is isentropic, find the velocity of the jet.