On the Calculation of External Aerodynamics: Industrial Benchmarks

The paper presents the-state-of-the-art numerical simulation of the flow around vehicles by examining a number of various industrial benchmarks. A selection of results, obtained by a finite volume numerical code based on the Reynolds-Averaged Navier Stokes (RANS) approach, illustrates the capability of Computational Fluid Dynamics (CFD) to provide accurate and reliable solutions in the area of external car aerodynamics. Benchmarks presented here are Peugeot 405 model, SAE Notchback Reference Body and VW-CFD model. Due attention was given to the reduction of both numerical as well as turbulence modeling error. This also includes the use of second-order accurate differencing schemes for convection terms and the full Reynolds-stress model to model Reynolds stresses. The computations showed a substantial difference in the flow patterns predicted by the standard k-ε model and by the full Reynolds-stress model. The Reynolds stress model predictions of the pressure distribution on the car body agree extremely well with the measurements. Some other details of the flow around car models are also well captured.