Subgrid-scale energy and pseudo pressure in large-eddy simulation

Abstract

A dynamic model based on the Germano identity is proposed to evaluate the subgrid-scale energy in large-eddy simulations as a function of the large-scale velocity field only. The model is shown to allow the satisfactory reconstruction of the total energy contained in a direct numerical simulation from large-eddy simulations with different resolutions. The predicted subgrid-scale energy is given as a simple algebraic expression based on the Leonard tensor appearing in the dynamic procedure and does not require an additional transport equation. The model assumes a Kolmogorov spectrum and is implemented with and without the introduction of a dissipation cutoff in the high wave vector range.