Abstract
The Dual-Mesh method for hybrid RANS/LES modelling is based on the execution of two distinct computations performed simultaneously on separate meshes that cover the same computational domain. One simulation corresponds to an unsteady Reynolds Averaged Navier-Stokes (RANS) model, while the other is a Large Eddy Simulation (LES). The two solutions are coupled using source terms (" drift terms ") in the corresponding sets of equations. In regions where the LES is under-resolved, the drift terms modify the LES equations to drive the solution towards that pertaining to the RANS equations. Vice-versa, in regions where the resolution is deemed sufficiently high for an LES, the drift terms modify the RANS equations and drive the corresponding solution towards the LES mean flow. Unlike other hybrid RANS/LES methods, the Dual-Mesh approach can be invariably used to alleviate resolution requirements near the wall, and for Embedded LES, where the LES approach is confined to a small portion of the domain, surrounded by a region modelled by RANS. In the present paper, we first validate the wall-modelling capability for an enclosed rotor-stator cavity, and then describe the application of an Embedded Wall-Modelled LES (EWMLES) for a jet in a crossflow. Comparisons with experimental velocity profiles available from the literature show a significant improvement obtained over Unsteady RANS (URANS) k − ω predictions.