Representing Subgrid Stress with Cinlar Velocity Field in Large Eddy Simulation

Abstract

In this paper, a new subgrid stress model for representing the small scale effects in large eddy simulation of incompressible flows is studied by using the energy spectrum for the Reynolds stresses and Taylor series expansion for the cross term. Cinlar random velocity field is based on vortex structures observed in the ocean at the subgrid scale. The energy spectrum of the random velocity field indicates a good match with the spectrum estimated from real data when the vortex diameter has right truncated Gamma distribution. The energy spectrum is parametrized in terms of the resolved velocity field to form the Reynolds stresses.