Large eddy simulation with adaptive r-refinement for the flow over periodic hills

Abstract

Using large eddy simulation (LES) instead of DNS potentially introduces modeling errors and discretization errors both depending on the step size of the grid. Hence it seems promising to optimize the grid in an LES via adaptation to minimize this effect. In contrast to classical grid adaptation, the LES equations depend on the grid via the subgrid-scale term and therefore change whenever the grid is changed, so that criteria for adaptation need to be LES-specific. The present work uses r-adaptive refinement, defined by redistribution of a given number of grid points in the computational domain.