Wind noise prediction of a car model through solutions of navier-stokes and FFOWCS williams & Hawkings equations

Gümüş, Baran
Vehicles are getting quieter by virtue of recent technological improvements, but still wind noise of vehicles is one of the major contributors of total vehicle noise. It must be limited to design quieter vehicles. Compared to aeroacoustic wind tunnel tests, suc-cessful aeroacoustic predictions are cheaper and more practical. Thus, accurate flow simulation and computational aeroacoustics (CAA) methods to predict vehicle aero-dynamic noise are investigated and discussed in this thesis. Moreover, accurate flow simulations are needed for successful aeroacoustic predictions and therefore higher order solution, mesh size limitation, appropriate boundary layer modelling and suitable turbulence modelling are required. Required flow simulation is performed by commer-cial FLUENT software. Subsequently, Ffowcs Williams & Hawkings (FW-H) method is used for far field wind noise calculation due to its robust and fast nature. Hence, aeroacoustic prediction is performed by a FORTRAN code for FW-H solution of far field wind noise. Results are compared to wind tunnel tests for verification. 


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Citation Formats
B. Gümüş, “Wind noise prediction of a car model through solutions of navier-stokes and FFOWCS williams & Hawkings equations,” M.S. - Master of Science, Middle East Technical University, 2017.