Leray simulation of turbulent shear layers

Abstract

We consider so-called Leray regularization of the convective contributions. This gives rise to a subgrid parameterization which involves both explicit filtering and (approximate) inversion. The Leray model also arises from the alpha-modeling strategy derived via Kelvin's circulation theorem. We study the dynamics associated with the Leray model in a turbulent mixing layer and compare predictions with filtered DNS results and findings due to dynamic (mixed) models. In particular, the kinetic energy, momentum thickness and energy-spectra are analyzed, establishing favorable performance of the Leray model and robustness at arbitrarily high Reynolds number. This is unique for a similarity-type model that does not contain an explicit eddy-viscosity term.