Study on the air jet wheel deflector system using state-of-the-art of Computational Fluid Dynamics (CFD) technique based on an open domain CFD software (OpenFOAM) is performed to reduce vehicle aerodynamic drag. Fabijanic’s simple vehicle model  is used for both the mesh sensitivity study and validation of current CFD technique. It was found that CFD method used in this study is reliable tool for the forecasting of the aerodynamic drag coefficient.
Parametric studies were conducted to investigate aerodynamic effects of the conventional wheel deflector and air jet wheel deflector system. For the conventional wheel deflector, 3.6% of drag reduction was achieved with a non-dimensional deflector height of 1/6, but the drag force tends to increase as the non-dimensional height increased. On the other hand, it was shown that air jet wheel deflector system can reduce vehicle aerodynamic drag up to 7.5% at the non-dimensional air jet velocity of 1.0.
Therefore it would be concluded that air jet wheel deflector is a useful device to reduce aerodynamic drag of automobile.