4. (16 marks total) fan 12 Mc bypass air ma LP turbine HP turbine compressor combustor The sketch shows a fan jet aircraft engine. A large flow of air enters the fan at T =0C, P = 100 kPa, and is compressed in the fan to P2-170 kPa. A portion of this air is then split off and is discharged through a nozzle at the back of the engine (the "bypass" air). The remaining air flow me (the "core" flow) then passes through the rest of the engine, comprising the compressor, the high pressure (HP) turbine which drives the compressor, and the low pressure (LP) turbine which drives the fan. The pressure P, -4200 kPa, and the temperature T-1400C. Assume that the isentropic efficiencies of the fan, the compressor and both turbines are all nc = n = 0.90. (a) (2 marks) Sketch a T-s diagram for this cycle. (b) (4 marks) If the exit temperature from the fan T, -322.7K, determine the compressor work in kJ/kg. (c) (3 marks) Noting that the high pressure turbine drives only the compressor, determine the temperature T, at the HP turbine outlet. (d) (4 marks) Calculate the pressure P, at the outlet of the HP turbine. (e) (3 marks) If the core mass flow 140 kg/s, determine the bypass flow . The low pressure turbine specific work is WTLP-480 kJ/kg and the fan specific work is w;= -50.2 kJ/kg. Use constant specific heat, assuming that for air C = 1.01 kJ/kg K, k=1.4.