Investigation of Turbulence Injection Methods in Large Eddy Simulation using a Compressible Flow Solver

Paper i proceeding, 2022

Three different methods for imposing velocity fluctuations in a compressible finite-volume solver are evaluated for zonal hybrid RANS-LES applications using the SA-IDDES model. The first method is a volume source term derived from an expansion of the time discretization of the fluctuating velocity component, suitable for an unstructured solver. The second method stems from an expansion of the convective flux of the fluctuating velocity component normal to the flow direction. The third methods considers a combination of both aforementioned methods. Additionally, a commutation term is derived for the convection term in the SA turbulence model in order rapidly reduce the turbulent viscosity across the RANS-LES interface. Good agreement with reference data is obtained with the investigated interface methods for the evaluated flow cases, which includes the turbulent channel flow and the zero-pressure-gradient boundary layer flow.