A Statistically-Derived Subgrid-Scale Kinetic Energy Model for the Large-Eddy Simulation of Turbulent Flows

A subgrid-scale (SGS) kinetic energy model for the large-eddy simulation (LES) of turbulent flows is constructed with the aid of the statistical results obtained from the two-scale direct-interaction approximation. In this model, the SGS Reynolds stress is written in terms of a generalized SGS eddy-viscosity representation which is expressed by using the SGS kinetic energy and the characteristic grid width. A model equation for the SGS kinetic energy is combined with the grid-scale Navier-Stokes and continuity equations to lead to an LES model of one-equation type. The usual Smagorinsky model is derived as its special case, and critical comparison is made between them.