Subgrid-scale pressure field of scale-enriched large eddy simulations using Gabor modes

Abstract

We cast the sub-grid velocity field in large eddy simulations as a sum of spatially localized stochastic modes, or Gabor modes, which are dynamically coupled to the resolved large-scale field. We evaluate the ability of the Gabor representation to reconstruct second order space-time statistics of the pressure field in homogeneous isotropic turbulence and find the reconstruction to be remarkably accurate in both a priori and a posteriori settings. The small number of modes required results in significant compression in degrees of freedom relative to solving the governing equations on a mesh capable of resolving all scales.