Comparison of isotropic and anisotropic subgrid scale models in Large Eddy Simulations of a backward‐facing step and square duct flow

Abstract

The present paper employs the anisotropic explicit algebraic subgrid‐stress model (EASM), proposed by Marstorp et al. J. Fluid. Mech. 639, 403 ‐ 432 (2009), developed in the spirit of an earlier explicit algebraic RANS‐model for statistical closures. The EASM in its elementary, computationally efficient non‐dynamic version is used for Large Eddy Simulation of three‐dimensional flows over a backward‐facing step at a bulk Reynolds number of 4805 and a square duct at 2205. Its performance is assessed by comparison with experimental data and an own Direct Numerical Simulation. Furthermore, a set of eddy‐viscosity models, including the recent σ‐model, is employed for comparison. Various statistical quantities are evaluated to assess the respective performance of the different models showing, that the anisotropic EASM compares favorably to the other models. (© 2016 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)