Modeling of the Reynolds-stress equations. 1. Return to the isotropydescription with the aid of direct numerical simulations data

E. P. Sukhovich

Institute of Physics, Latvian Academy of Sciences, Salaspils-1, LV-2169, Latvia

Abstract
The paper develops proposals for a model of turbulence in which the Reynolds stresses are determined from the solution of transport equation for these variables. Particular attention is given to the approximation of the return to isotropy part of the pressure-strain correlation. A quadratic nonlinear model of Sarcar and Speziale for the slow pressure-strain correlation is used. The constants of model are evaluated from direct numerical simulation data of Mansour, Kim and Moin for developed channel flow. An added relation between coefficients is derived from an analysis of behaviour pressure-strain correlation in limiting case of one-dimensional turbulence. It is demonstrated that coefficients of model are function of second and third scalar invariants of the anisotropy tensor. The model proposed in this study successfully captures the DNS data. Comparisons are also made with the predictions of other models. The accuracy of proposed model is considerably more than accuracy of models proposed in the literature.Figs 3, Refs 13.