The simulation of broadband noise with a RANS based CAA method is discussed. A stochastic sound source modeling is performed using the Random Particle Mesh (RPM) method. The RPM method is applied to slat trailing edge noise on a three-element high-lift system for commercial aircraft. RANS simulations provide mean-flow and statistical properties of the turbulence by a two-equation turbulence closure to generate stochastic sound source. The sound sources are generated on a streamline oriented auxiliary mesh and reproduce typical two-point correlation functions of the turbulence velocity fluctuations. The sound propagation is computed by the acoustic perturbation equations (APE), which are solved in time-domain with a high-order dispersion related preserving (DRP) scheme on a multi-block structured grid. An extensive set of CAA simulation is performed to identify and evaluate slat noise source mechanisms. Velocity and angle of attack dependencies of the noise mechanism are examined and the effect of sweep angle is discussed. The aeroacoustic simulations are validated against large-scale wind-tunnel measurements.
展开▼
