Numerical investigation of flows around an axisymmetric body of revolution by using Reynolds-stress model based hybrid Reynolds-averaged Navier–Stokes/large eddy simulation

Abstract

Flows around an axisymmetric body of revolution at a zero yaw angle were studied using a hybrid Reynolds-averaged Navier–Stokes (RANS)/large eddy simulation (LES) approach, which employed a full Reynolds stress model (RSM) in the RANS branch with the aim of accounting for the Reynolds stress anisotropy, streamline curvature, and flow separations in the boundary layer. The SUBOFF model without appendages was applied to conduct the simulations, and the Reynolds number based on the free-stream velocity and the length of the body is ReL=1.2×106. The results, including time-averaged Cp, Cf, and velocity statistics, were compared with the experimental data and wall-resolved LES results available in the literature, and the overall agreement of the comparisons was satisfactory. To assess the performance of the RSM-based hybrid RANS/LES approach, we carried out shear-stress transport-based hybrid RANS/LES approach simulations under identical free-stream conditions for comparison. The sensitivity of the hybrid RANS/LES approach to the RANS models was observed for separated flow with surface curvature and adverse pressure gradient-induced separation. The RSM-based hybrid RANS/LES approach was found to provide a better prediction for the unsteady flows near the stern. That is because the effects of the streamline curvature and the strong interactions between individual stresses can be captured by the exact production terms in the RSM-based hybrid RANS/LES approach. These effects are important for predicting the development of turbulent boundary layers along the stern.