One of the techniques used in STOL fighters is the flap-blowing turbofan engines. Air is bled...

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One of the techniques used in STOL fighters is the flap-blowing turbofan engines. Air is bled from the LPC and ducted to the flap system in the wing trailing edge. Such accelerated air flow creates greater lift than would be possible by the wings themselves. Here is the data for one of these engines. During takeoff at sea level (T = 288 K, P = 101 kPa), the engine has a BPR of 3.0 and the core engine air flow is 22.7 kg/s. Fifteen percent of this air is bled at the exit of the LPC. The component efficiencies are given as ne = 0.88, n = 0.90, 776=0.96, 7=0.94, 7m=0.95 The total pressure recovery factor of the diffuser (related to the free stream) is rd = 0.98, compressor total pressure ratio is 15, fan total pressure ratio is 2.5 maximum allowable turbine- inlet temperature is 1,400 K, total pressure loss in the combustor is 3%, and heating value of the fuel is 43,000 kJ/kg. Assume the working medium to be air and treat it as a perfect gas with constant specific heats. Compute the following a) The properties at each section b) The thrust force Bleed air L.P. compressor Variable pitch fan c) The TSFC d) The overall efficiency Augmentor flap system One of the techniques used in STOL fighters is the flap-blowing turbofan engines. Air is bled from the LPC and ducted to the flap system in the wing trailing edge. Such accelerated air flow creates greater lift than would be possible by the wings themselves. Here is the data for one of these engines. During takeoff at sea level (T = 288 K, P = 101 kPa), the engine has a BPR of 3.0 and the core engine air flow is 22.7 kg/s. Fifteen percent of this air is bled at the exit of the LPC. The component efficiencies are given as ne = 0.88, n = 0.90, 776=0.96, 7=0.94, 7m=0.95 The total pressure recovery factor of the diffuser (related to the free stream) is rd = 0.98, compressor total pressure ratio is 15, fan total pressure ratio is 2.5 maximum allowable turbine- inlet temperature is 1,400 K, total pressure loss in the combustor is 3%, and heating value of the fuel is 43,000 kJ/kg. Assume the working medium to be air and treat it as a perfect gas with constant specific heats. Compute the following a) The properties at each section b) The thrust force Bleed air L.P. compressor Variable pitch fan c) The TSFC d) The overall efficiency Augmentor flap system

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To solve the given problem we need to perform a thermodynamic analysis of the engine Well calculate the properties at each section the thrust force the thrust specific fuel consumption TSFC and the ov... View the full answer