Porous treatment to mitigate trailing edge noise
* Präsentierender Autor
Zusammenfassung:The present contribution deals with the numerical analysis of the application of porousmaterials to reduce the turbulent boundary layer trailing edge noise. The aerodynamicallygenerated sound is simulated by a hybrid two-step LES/CAA method, where the rigid frameporous material is treated by the method of volume averaging in the Navier-Stokes andthe acoustic perturbation equations, thus defining continuously varying flow and acoustic statevariables inside the porous media. A NACA 0012 airfoil with a sharp trailing edge at zero angle-of-attack at a Reynolds number of 1·10^6 in a low Mach number flow of 0.01 is considered, to isolatethe broadband noise contribution from the bluntness noise. The LES domain will coverthe last 20% of the chord. A preceding 2D RANS simulation together with a synthetic eddygeneration method will provide the inflow data for the LES. The noise mitigation potential willbe evaluated by comparing a solid baseline configuration, for which reference data exists in theliterature, against an airfoil, whose rear part is made of a realistic porous material, calibratedbeforehand, in terms of the near far field acoustics. The acoustical benefit will be discussed withsimultaneous consideration of the effects on the aerodynamic performance.