Prediction of nonequilibrium turbulent flows with explicit algebraic stress models

An explicit algebraic stress equation, developed by Gatski and Speziale, is used in the framework of the K-UJ and K-e formulations to predict two-dimensional separated turbulent flows. The nonequilibrium effects are modeled through coefficients that depend nonlinearly on both rotational and irrotational strains. The proposed models were implemented in the Courant-Friedrichs-Lewy three-dimensional Navier-Stokes code. Comparisons with the experimental data are presented, which clearly demonstrate that explicit algebraic stress models improve the response of standard two-equation models to nonequilibrium effects. I. Introduction