A RANS-based statistical noise model for trailing edge noise

Abstract

A RANS (Reynolds averaged Navier-Stokes)-based statistical noise model (RSNM) is used to calculate the trailing edge noise produced by NACA 0012 and DU 96-180 airfoils, at various angles of attack and ow velocities. The method uses a Green's function for a semi-in nite half-plane to generate a far- eld acoustic autospectrum using a statistical model for the turbulence in the boundary layer in the vicinity of the trailing edge. This statistical model is an assumed turbulent velocity cross spectrum, and is de ned in terms of the mean ow data provided by a RANS simulation. Reasonably good agreement is observed between acoustic predictions and experiments for the NACA 0012 cases. For the DU 96-180, the model over-predicts the experimental acoustic spectra.