Backward-facing step calculations using the shear improved Smagorinsky model

Recently a simple modification of the standard Smagorinsky model was proposed that takes into account the physics associated with strong shear in wall-bounded flows. After its initial proposal in Toschi et al. (2000) the model was first tested in Leveque et al. (2006) in the context of channel flow. Here we test its validity on the more complex backward-facing step geometry. We compare results against experimental data, DNS data, and results obtained with the dynamic model. The model gives accurate results, comparable with those achieved with the dynamic model, at the low Reynolds number of the computations. We identified several issues that should be addressed in order to broaden the applicability of the model to non-stationary flows.