Abstract
Vortical and turbulent structures for the KVLCC2 at a range of drift angles are studied using various convection schemes coupled with algebraic Reynolds stress detached eddy simulation (ARS-DES) turbulence models. The convection schemes and the turbulence models are evaluated quantitatively using rigorous verification and validation (V&V), including comparisons with available EFD data. For 0˚ drift, the integral forces are most accurately predicted by the fourth order (hybrid) interpolation scheme (FD4h) coupled with ARS but the local quantities (velocities and turbulent quantities) are best predicted by the second order TVD scheme with Superbee limiter coupled with ARS (TVD2S-ARS). For 12˚, the local quantities and the integral forces and moments are most accurately predicted by TVD2S-ARS. The vortical structures are also least dissipated when computed with TVD2S-ARS at 12˚ and 30˚ drift angles. Turbulent structures are analyzed using ARS-DES model with a pure FD4 scheme. The turbulent kinetic energy (TKE) and Reynolds stresses peak near the separation point at the bow and within a certain distance to the vortex core of all the vortices. Near the bow, turbulent structures are similar to those for a separated turbulent boundary layer and the recirculation region of a backward-facing step flows. Overall Reynolds normal stresses have similar distribution and magnitude compared to TKE. uw and vw are an order of magnitude smaller than uv , which has the same order of magnitude with the normal stresses. TKE and Reynolds stresses reach a local maximum right after the vortex breakdown points for helical vortex tubes and are intensified along the vortex core further downstream, likely due to the enhanced unsteady oscillation caused by the helical instability, which is consistent with previous studies on vortex breakdown for flows over a delta wing.