Direct- and Large Eddy Simulations of Turbulent Flow in CS0 Diffuser on Resolved and Under-resolved Meshes

A Direct Numerical and Large Eddy Simulation study is conducted to establish the NASA CS0 diffuser as a test case for scale-resolving simulation methods and to evaluate the ability of such simulations to accurately predict flows with adverse pressure gradients and shallow separation from a smooth surface. The results of fine grid studies are in a good agreement with experimental data and substantially supplement them. These data are used as a basis for testing of LES on reduced grids, using different combinations of wall treatments and turbulence model formulations.