An IDDES study of the near-wake flow topology of a simplified heavy vehicle

Abstract The complex wake flow of a GTS (ground transportation system) model contributes to large percentage the aerodynamic drag force. Therefore, predicting accurate will help carry out reduction strategies. In this paper, near-wake topology was studied at Re = 2.7×104 assess capability hybrid RANS/LES (Reynolds-averaged Navier–Stokes/large eddy simulation) approach, known as IDDES (improved delayed detached simulation). current study also aims understand effects different computational parameters, e.g. spatial resolution, time step, residual level, discretization scheme and turbulence model, on asymmetrical configuration. A comparison with previous water channel tests, well-resolved LES, partially averaged Navier–Stokes URANS (unsteady RANS) included better benefits approach. results show that medium fine grids, produces an (known state I) in vertical midplane, reported studies. recommended parameters for step (1×10–4 s) level (1×10–4) provide sufficient accuracy predictions good agreement experiments. For convective term momentum equation IDDES, bounded central difference is proposed be adopted discretization. Additionally, cannot accurately capture field. proves capable field simplified heavy vehicle high accuracy. All obtained conclusions can references GTS.