Towards the prediction of broadband trailing edge noise

Kurzfassung

Trailing edge noise is simulated based on acoustic perturbation equations and a stochastic model for artificial turbulence that determines the acoustic broadband sources. The acoustic equations are integrated applying CAA techniques and subsequently a Kirchhoff extrapolation to the far-field. The sound generation mechanism is based on the interaction of vortical structures with the trailing edge. In the first presented approach, the vortical structures are induced by stochastic field or volume source terms. In the second approach, a stochastic incident surface velocity model is deduced from the volume sources that allows to prescribe the acoustic sources over the wall boundary condition rather than through right-hand side field sources. This way the resolution requirements of the acoustic sources are reduced by one spatial dimension and the computational effort to evaluate them is greatly decreased. Both source approaches compare quite well for trailing edge noise.