Large Eddy Simulation of Sound Sources on a Cambered Airfoil

Abstract

n the framework of MGLET, Wall-Modeled LES is ap-plied and validated on a cambered airfoil, i.e., DU96-180.The onset of turbulence for the WMLES is facilitated byapplying roughness on the profile. The significance ofthis roughness on the near-wall flow and far-field acous-tics are discussed. In contrary to the observations madein Larsson et al. (2016), the SPL prediction is not only lim-ited uptof=uτ/δrather across a wide range of frequen-cies. The sound pressure level spectrum shows a goodagreement to the experimental data reported in BANC-II. Furthermore, the prediction capabilities of the WM-LES is further verified on a noise reduction by retro-fittedserrations. The method reproduces the widely reported effect of serrations, i.e., a reduction in low-mid frequencyranges and an additional noise in higher frequencies.

The study strongly advocates for the use of WMLES as a highly effective scale resolving simulation method,capable of producing the relevant near-wall and far-fieldphysics, required for accurate sound prediction from air-frame components