Slat Noise Predictions Based On APE And Stochastic Sound Sources From RANS

Kurzfassung

Slat Noise simulations are carried out for a high-lift airfoil. A low-cost Computational Aeroacoustics (CAA) approach is applied, which is based on acoustic perturbation equations (APE) in the time-domain that are forced by stochastic sound sources. The newly developed stochastic model is based on the spatial convolution of white-noise and reproduces very accurately target distributions of turbulence kinetic energy and length scales as provided by a steady RANS computation of the turbulent flow problem. The method is applied to simulate spectra and directivities of the slat noise problem. The Mach number scaling law of the broadband slat noise component is evaluated based on three different freestream velocities (M=0.088, 0.118, 0.165). The acoustic benefit of a slat cove cover on broadband sound generation is numerically studied.