Detached-Eddy Simulation Based on the v-f Model

Abstract: Detached-eddy simulation (DES) based on the v-f Reynolds-averaged Navier-Stokes (RANS) model is developed and tested. The v-f model incorporates the anisotropy of near-wall turbulence, which is absent in other RANS models commonly used in the DES community. The v-f RANS model is modi ed in order that the proposed v-f -based DES formulation reduces to a transport equation for the subgrid-scale kinetic energy in isotropic turbulence. First, three coe cients in the elliptic relaxation equation are modi ed, which is tested in channel ow with friction Reynolds numbers up to 2000. Then, the proposed v-f DES model formulation is derived. The constant, CDES, required in the DES formulation was calibrated by simulating both decaying and statistically-steady isotropic turbulence. After CDES is calibrated, the v -f DES formulation is tested for ow around a circular cylinder at a Reynolds number of 3900, in which case turbulence develops after separation. Simulations indicate that this model represents the turbulent wake nearly as accurately as the dynamic Smagorinsky model. For comparison, Spalart-Allmaras-based DES is also included in the cylinder ow simulation.