A posteriori tests of subgrid-scale models in an isothermal turbulent channel flow

TL;DR

This study evaluates various subgrid-scale models in large-eddy simulations of isothermal turbulent channel flow, introducing new models and analyzing their performance against direct numerical simulations at different mesh resolutions.

Contribution

The paper proposes new zero-equation subgrid-scale models and assesses their effectiveness in LES of turbulent channel flow without wall functions.

Findings

Models improve LES accuracy over no-model simulations

Functional models benefit from dynamic tensorial methods

Performance varies with mesh resolution and model type

Abstract

This paper studies the large-eddy simulation (LES) of isothermal turbulent channel flows. We investigate zero-equation algebraic models without wall function or wall model: functional models, structural models and mixed models. In addition to models from the literature, new models are proposed and their relevance is examined. Dynamic versions of each type of model are also analysed. The performance of the subgrid-scale models is assessed using the same finite difference numerical method and physical configuration. The friction Reynolds number of the simulations is 180. Three different mesh resolutions are used. The predictions of large-eddy simulations are compared to a direct numerical simulation filtered at the resolution of the LES meshes. The results are more accurate than a simulation without model. The predictions of functional eddy-viscosity models can be improved using constant-parameter or dynamic tensorial methods.