Scale-Resolving Simulations with a Low-Dissipation Low-Dispersion Second-Order Scheme for Unstructured Finite-Volume Flow Solvers

Abstract

A new low-dissipation low-dispersion 2nd-order scheme is applied to scale-resolving flow simulations using compressible and incompressible unstructured finite-volume solvers. In wall-resolved and wall-modeled LES computations of the channel flow the new scheme yields substantial improvements compared to the more dissipative/dispersive basic central scheme over a considerable range of Reynolds numbers. For general hy- brid RANS/LES simulations a numerical blending approach is applied which uses a local sensor function to switch between the new scheme in LES regions and the basic central scheme in the outer flow field. After an a-priori determination of a consistent sensor function, the hybrid numerical scheme is used to simulate a backward-facing step flow, where satisfactory results and reduced grid sensitivity are obtained. To demon- strate its potential in relevant aeronautical flows, the new scheme is successfully applied to hybrid RANS/LES computations of a 3-element airfoil near stall and a rudimentary landing gear with massive flow separation. Note that this paper is jointly published with a companion paper by Löwe et al., in which the low-dissipation low-dispersion 2nd-order scheme is derived and theoretically analyzed, followed by a basic assessment for fundamental numerical test cases.