Large Eddy Simulation of Plane Channel Turbulence Using Dynamic Two-Coefficient Mixed Subgrid-Scale Models.

A reliable subgrid-scale (SGS) model and a higher order accurate discrete method are required for the large eddy simulation (LES) of practical problems. At least fourth-order accuracy is needed for the LES using a finite difference method, because SGS stress seems to be a second-order product of filter width. However, the LES using a fourth-order accurate finite difference method and a dynamic Smagorinsky model (DSM) does not give proper solutions in cases of poor resolution. This indicates that the reliability of the DSM is insufficient for the LES of practical problems. In this paper, a dynamic two-coefficient mixed SGS model (DTMM) and a revised model (DTMMR) of the DTMM are constructed. The DTMMR is proposed as a better SGS model than the DSM and DTMM through the LES of plane channel turbulence at Reynolds numbers (based on the channel half-width and friction velocity) 180 and 650.