RANS-DES Comparison on the Numerical Modelling of a Downforce Generating Wing Moving over a Solid Surface

Abstract

Present paper covers the numerical modelling of a 3D wing operating near a solid surface using Reynolds Averaged Navier Stokes (RANS) and Detached Eddy Simulation (DES). The characteristics of the flow over a wing near a surface is significantly different from the free flight. Capturing the changing aerodynamics of an object moving close to a surface have importance for flight and vehicle aerodynamics. This study aims to investigate the reliability of RANS and DES turbulence modelling approaches on the numerical solution of the challenging ground effect flow physics of the downforce generating (or inverted) wings. For this purpose, a 3D symmetrical wing moving in the close proximity of a solid surface is numerically modelled in fully turbulent flow conditions. The results show that, DES approach predicts the lift force slightly better than RANS. On the other hand, tip leakage flow capturing and the separating vortex field modelling of the DES approach is clearly superior. Comparison of velocity, vorticity and the vortex visualization results are presented for the better understanding of the performance of the two modelling approaches.