A new subgrid eddy-viscosity model for large-eddy simulation of anisotropic turbulence

Abstract

A new subgrid eddy-viscosity model is proposed in this paper. Full details of the derivation of the model are given with the assumption of homogeneous turbulence. The formulation of the model is based on the dynamic equation of the structure function of resolved scale turbulence. By means of the local volume average, the effect of the anisotropy is taken into account in the generalized Kolmogorov equation, which represents the equilibrium energy transfer in the inertial subrange. Since the proposed model is formulated directly from the filtered Navier–Stokes equation, the resulting subgrid eddy viscosity has the feature that it can be adopted in various turbulent flows without any adjustments of model coefficient. The proposed model predicts the major statistical properties of rotating turbulence perfectly at fairly low-turbulence Rossby numbers whereas subgrid models, which do not consider anisotropic effects in turbulence energy transfer, cannot predict this typical anisotropic turbulence correctly. The model is also tested in plane wall turbulence, i.e. plane Couette flow and channel flow, and the major statistical properties are in better agreement with those predicted by DNS results than the predictions by the Smagorinsky, the dynamic Smagorinsky and the recent Cui–Zhou–Zhang–Shao models.