CAN REYNOLDS STRESS TRANSPORT MODELS BE USED FOR LARGE EDDY SIMULATION?

etc15 Tracking Number 191

This work explores a route to unify Reynolds averaged (RANS) and large eddy simulation (LES). The approach is to use a slightly modified Reynolds stress transport model for any mesh resolution. The model is formulated in terms of both total kinetic energy and modeled kinetic energy in such a way that the RST model correctly reproduces RANS results, LES results, and even DNS results (by turning itself off). The model equations do not contain functions of the mesh size within any of the model terms or constants. It is demonstrated that this approach works at any mesh resolution. In addition, the model naturally transitions between mesh resolutions, either coarse to fine or vice-versa. It is shown that for LES mesh resolutions the model returns a turbulent length scale that is proportional to the mesh size (the classic LES turbulent length scale).