Large eddy simulation of the flow around an inclined prolate spheroid

Abstract

Results from a computational study of high-Reynolds-number (Re = 4.2 × 10⁶) flow through a 6:1 prolate spheroid, based on large eddy simulation (LES), are presented here. The objectives are to evaluate the applicability of LES to practically relevant high-Re flows, to investigate the influence of subgrid modelling and grid resolution on the quality of the results and to discuss the fluid dynamics of this particular flow. The LES use a variety of subgrid and wall models and, here, they were performed on different grids in appropriate combinations. The first subgrid model used was a k-equation eddy-viscosity model for parametrization of the subgrid stress tensor, used with and without the wall model. Additionally, the localized dynamic Smagorinsky model was applied to investigate the capabilities of a zero-equation model. In combination with these models, two grid variants were used: one baseline grid and a uniformly refined grid. The computational domain consists of a large sphere in which the spheroid is embedded and the LES equations were solved using a finite-volume-based solver for the filtered incompressible Navier–Stokes equations. Simulations were performed at 10° and 20° angles of attack, and comparison with experimental data was carried out for both pressure and velocity. Reasonable agreement, taking into account the mesh resolution and the different models, was found for both angles of attack.