A single-spool turbojet engine with an inoperative afterburner is rated at 12.12 KN at an altitude...

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A single-spool turbojet engine with an inoperative afterburner is rated at 12.12 KN at an altitude of 9150 m, where the ambient conditions are 32 kPa and 240 K. The pressure ratio across the compressor is 12 and temperature at the turbine inlet is 1400 K. The aircraft speed is 310 m/s. Assume unchoked nozzle and constant specific heat in all processes with y= 1.4, cp = 1.05 kJ/kgK and R = 287 J/kgK. The heating value of the fuel is 42,700 kJ/kg. All the processes are assumed ideal and no pressure is lost either in the combustion chamber or in the inoperative afterburner as such: Isentropic efficiency of the diffuser and nozzle Isentropic efficiency of the compressor Isentropic efficiency of the turbine Mechanical efficiency Ratio of compressor power to the turbine power Pressure losses in the combustor Combustor efficiency (b) Calculate the fuel-to-air ratio (c) Calculate the velocity of the exhaust gases (a) Draw schematically a turbojet engine and label its different components. Then, sketch the T-s diagram for the thermodynamic cycle of this turbojet engine. [5 marks] (d) Calculate the air mass flow rate 1 (e) Calculate the propulsive, thermal and overall efficiencies 1 1 1 1 0% 1 [12 marks] [13 marks] [5 marks] [5 marks] A single-spool turbojet engine with an inoperative afterburner is rated at 12.12 KN at an altitude of 9150 m, where the ambient conditions are 32 kPa and 240 K. The pressure ratio across the compressor is 12 and temperature at the turbine inlet is 1400 K. The aircraft speed is 310 m/s. Assume unchoked nozzle and constant specific heat in all processes with y= 1.4, cp = 1.05 kJ/kgK and R = 287 J/kgK. The heating value of the fuel is 42,700 kJ/kg. All the processes are assumed ideal and no pressure is lost either in the combustion chamber or in the inoperative afterburner as such: Isentropic efficiency of the diffuser and nozzle Isentropic efficiency of the compressor Isentropic efficiency of the turbine Mechanical efficiency Ratio of compressor power to the turbine power Pressure losses in the combustor Combustor efficiency (b) Calculate the fuel-to-air ratio (c) Calculate the velocity of the exhaust gases (a) Draw schematically a turbojet engine and label its different components. Then, sketch the T-s diagram for the thermodynamic cycle of this turbojet engine. [5 marks] (d) Calculate the air mass flow rate 1 (e) Calculate the propulsive, thermal and overall efficiencies 1 1 1 1 0% 1 [12 marks] [13 marks] [5 marks] [5 marks]