The Simulation Of Slat Noise Applying Stochastic Sound Sources Based On Solenoidal Digital Filters (SDF)

Abstract

A new fast and cheap stochastic approach is introduced to model the unsteady turbulent sound sources in the slat-cove of a high-lift airfoil. It is based on the spatial filtering of a random white-noise field and incoporates information about the integral length scale and the turbulent kinetic energy from a steady RANS computation. The stochastic method yields a solenoidal velocity field that is capable to reproduce exactly the well known analytical solution of the second-order two-point correlation tensor in case of homogeneous isotropic turbulence. Results for the sound generation at the slat are given for the underlying RANS mean-flow field being based on a Menter SST turbulence model with Kato-Launder modification. The results for the modeled turbulent flow-field and the radiated acoustic field exhibit physical meaningful characteristics.