Evaluation of the Spectral Element Dynamic Model for Large-Eddy Simulation on Unstructured, Deformed Meshes

Abstract

In this paper, the Spectral-Element Dynamic Model (SEDM), suited for Large-Eddy Simulation (LES) using Discontinuous Finite Element Methods (DFEM), is assessed using unstructured meshes. Five test cases of increasing complexity are considered, namely, the Taylor-Green vortex at Re = 5000, the turbulent channel flow at Reτ = 587, the circular cylinder in cross-flow at ReD = 3900, the square cylinder in cross-flow at ReD = 22400 and the channel with periodic constrictions at Reh = 10595. Various discretization parameters such as the grid spacing, polynomial degree and numerical flux are assessed and very accurate results are reported in all cases. This consistency in the results demonstrates the versatility of the SEDM approach and its ability to gage the actual resolution and quality of the mesh and, accordingly, to introduce an amount of sub-grid dissipation which is adapted to the spatial discretization considered.