hp -adaptive hybrid RANS/LES simulations for unstructured meshes with the discontinuous Galerkin method

Abstract

In this paper, an hp-adaptation strategy designed for discontinuous Galerkin methods is applied to hybrid RANS/LES simulations. The 3D hp-adaptive strategy is suited for tetrahedral and hybrid prismatic/tetrahedral meshes, and relies on a metric-based remeshing approach. The metric field and the polynomial map of the adapted meshes are built from an a posteriori error estimator which couples the measure of the energy associated with the highest-order modes and the inter-element jumps, combined with a smoothness sensor which guides the choice between hand p-adaptation. The turbulence modelling relies on a Zonal Detached Eddy Simulation approach (ZDES mode 1). The resolution requirements in terms of minimum wall spacing Δ𝑦 + are first assessed from steady RANS flat plate simulations at Reynolds 5 • 10 6 and the value of the DES constant is assessed for DG from 3D Taylor-Green vortex flow simulations at Reynolds 5000. The developed hp-adaptation algorithm is then applied to hybrid RANS/LES simulations of the PPRIME nozzle configuration at diameter-based Reynolds 10 6 , starting the adaptive process from previously RANS-adapted meshes.

An implicit p‐adaptive discontinuous Galerkin solver for CAA/CFD simulations

“…However, the industrial interest for these methods has been strongly promoting research efforts to increase their efficiency 8‐12 . Previous works contributed to the development of efficient high‐order numerical methods for steady and unsteady flow problems involving adaptation of the spatial discretization by varying the order of the polynomial approximation throughout the domain, for example, References 13‐17, by performing mesh adaptation, for example, References 18‐22, or both, for example, References 23,24.…”