Advanced techniques for grau area mitigation in DES simulations and their effectes on the subsonic round jet acoustic spectra

Abstract

The research dedicated to the investigation of different gray-area mitigation approaches towards accurate aerodynamics and aeroacoustics is presented. The recent modifications of hybrid RANS-LES DDES approach based on combinations of new adapting subgrid length scales (~ !, SLA and lsq) and LES models ( and S3QR) are considered. The object of investigation is an immersed subsonic turbulent jet. The simulations are carried out on a set of refining meshes using two different scale-resolving numerical algorithms realized in the compressible codes NOISEtte and OpenFOAM. The evaluation of different approaches is focused on the analysis of far field noise. The results show that all the considered techniques provide appropriate accuracy to predict the noise generated by the turbulent jet. The study clearly demonstrated the importance of both numerical scheme and subgrid turbulence model. The peculiarities of considered approaches are revealed and discussed.