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A subgrid-scale model for LES based on the physics of interscale energy transfer in turbulence
The scale-similarity model in large-eddy simulation (LES) leads to an attractive, functionally simple expression for the subgrid-scale (SGS) stress tensor. It is well known, however, that it does not accurately predict the subgrid-scale dissipation leading to its failure in actual LES. In the present work, considerations of interscale energy transfer have been used to identify sources of the observed deficien- cies of the similarity model, allowing to develop a new interscale transfer model with favorable characteristics of SGS dissipation. The proposed model maintains the functional simplicity of the similarity model, consisting of test-filtered velocities and their products, but offers clear improvements in predictions of mean flow quantities and the global energy flux from the resolved to subgrid scales without the need for additional eddy viscosity terms to augment SGS energy dissipation. The application of the interscale transfer model in LES of wall-bounded flows leads to predictions of mean and RMS flow quantities comparable to those obtained for other, established SGS models.Author(s):
Julian Andrzej Domaradzki
University of Southern California
United States
Brian Wayne Anderson
University of Southern California
United States