emmo1210 Posted May 18, 2006 Report Share Posted May 18, 2006 hi guys. new to the forum. im a mechanical engineer in the polymer sector by trade, but have been asked by by my nephew now studing engineering a turbofan question and need a little nudge in the right direction His question reads An aircraft powered by turbofan engines cruises at a Mach No. of 0.82, at an altitude where Ta = 223.3K and Pa = 0.265 bar. Each engine has a by-pass ratio of 4.8 and a total mass flow rate of 210 kg/s at these conditions. The fan pressure ratio is 1.75 and the fan efficiency is 97%. The intake efficiency is 94% and the by-pass nozzle efficiency is 100%.Calculate the thrust from one of the engines produced by the by-pass air alone. now i understand that the thrust is going to be a combination of the bypass and the main core thrust.I can get the compressor work but the problem which i am having is figuring the turbine entry temperature. can any of you pros out there assist much appreciated Quote Link to comment Share on other sites More sharing options...
UncleAl Posted May 18, 2006 Report Share Posted May 18, 2006 Adiabatic compression plus stall energy is a good start to decorate air specific heat. Mass flow is too fast to lose much heat during compression (a running engine is at equilibrium anyway). What is the mass throughput speed at the fan compared to Mach 0.82? Quote Link to comment Share on other sites More sharing options...
emmo1210 Posted May 18, 2006 Author Report Share Posted May 18, 2006 the mass air flow through the fan is 210kg/s and with a bypass ratio of 4.8 it means the mass flow of air throguh the compressor is 210/4.8 = 43.75 kg/s. im sorry this is really a new field to me. is this the info you required? Quote Link to comment Share on other sites More sharing options...
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