MODELLING OF AN AERODYNAMIC NOISE PROPAGATION BY MEANS OF AN IN-HOUSE CAA CODE

Abstract

The compressible Navier-Stokes equations can numerically predict the aerodynamic as well as acoustic flow field simultaneously. The solution of the Navier-Stokes equations using DNS or LES methods for capturing both the aerodynamic and acoustic fluctuations is still very time consuming. Since there is a large disparity of the length and time scales between the aerodynamic and acoustic variables the DES and LES methods are usually used for the source domain, it means there, were the aerodynamic disturbances generate noise. For the rest of computational domain, where the acoustic waves propagate the other methods can be used, e.g. the non-linearized Euler equations for fluctuating (acoustic) variables (Dykas et al.200