Prediction of airfoil trailing edge noise reduction by application of complex porous material

Abstract

Reduction of noise generated at geometric edges can be achieved by replacing solid material with porous inlays. The acoustic benefit for airfoil trailing edge noise was experimentally found to yield a reduction in sound pressure level of approximately 6, dB. Numerical methods are of interest to find optimal properties of the porosity. A successful method of modeling porous materials is the volume-averaging approach. Prior simulations have been enhanced by implementing a modified numerical treatment of the interface between the free fluid and the porous parts to model the interaction of the acoustic and flow quantities in these two regimes. Furthermore, numerical simulations have been run to show the influence of an anisotropic, respectively non-uniform porous trailing edge on the emitted sound.