Based on large eddy simulation and FW-H(Ffows Williams-Hawkings) acoustics simulation

the unsteady flow field and the jet noise distribution of overall sound pressure level(OASPL) were obtained for one 1/10 scaled turbofan engine with separated exhaust system at various bypass offset distances.It shows that the structure of bypass offset has the ability of depressing the exhaust jet noise.The noise depression effects have relation with the bypass offset distance.Exhaust jet noise is reduced from 146.7dB to139.5dB at the offset distance of 0.15D which is the maximal noise reduction.The configuration and the numerical method mentioned can be taken into consideration in the design of the separated exhaust for turbo-fan engine.