Formulation of Subgrid Stochastic Acceleration Model (SSAM) for LES of a High Reynolds Number Flow

Abstract

In this paper, we proposed a new subgrid scale (SGS) model in large eddy simulation (LES) of a high Reynolds number turbulent flow. The traditional approaches are usually based on modeling of the non-resolved velocity field, and are customary invariant on the Reynolds number. When the Reynolds number is high, the flow at subgrid scales is intermittent and its structure is depending on the Reynolds number. To account for this, the new SGS model is focused on simulation of the non-resolved acceleration of fluid particle. With this model, an approximation of unfiltered velocity field is reconstructed by computation of the instantaneous model-equation introduced in the paper. The performed computation of a high Reynolds number stationary homogeneous turbulence reproduced qualitatively the effects of intermittency recently observed in experimental studies.