Flow simulations of generic vehicle model SAE type 4 and DrivAer Fastback using OpenFOAM

Abstract

The aim of this study is to simulate flow over two types of generic vehicle model. The simulation is done using the open source CFD solver, OpenFOAM, which is based on the finite volume method, where each of the control volume is treated for its flow physical conservation using governing equations. The two different generic vehicle models are SAE Type 4 (fullback) - strongly simplified model and DrivAer Fastback - a more realistic vehicle model. Their flow structures are compared based on the CFD results. The different in flow behaviours are shown clearly by each model due to the geometry differences, where the SAE Type 4 is blunter, while the DrivAer Fastback is more aerodynamic. Results showed that SAE Type 4 model able to produce large turbulence wake structures and thus lead to higher value of drag coefficient compared to the DrivAer Fastback model. The drag coefficient for the SAE Type 4 is 0.3722 and the DrivAer Fastback is 0.2803.