Constrained Large Eddy Simulation of Wall-Bounded Turbulent Flows

Abstract

We present a novel simulation tool-constrained large eddy simulation (CLES), for numerical experiments on the wall-bounded turbulent flows. Different from the traditional large eddy simulation(LES) and the available hybrid RANS/LES approaches, the CLES method computes the whole flow domain by solving the LES equations with a Reynolds-stress-constrained (RSC) subgrid-scale (SGS) stress model in the near-wall region and a traditional SGS stress model in the rest.The CLES approach is validated by simulating the turbulent channel flow and flow around a circular cylinder. With the same grid resolutions, CLES can successfully simulate all these flow regimes as well as DES and other available methods. For the case of attached flows, CLES is able to eliminate the non-physical Log-Layer Mismatch problem in traditional hybrid RANS/LES methods successfully, and to predict mean velocity profile, turbulent stresses and skin friction coefficient more accurately compared with the DES. For the case of detached flows, the performance of CLES is comparable to DES.