Influence of cooling exit flow on aerodynamic performance with different outlet layouts

Experimental and numerical methods were performed to investigate the influence of engine-cooling exit flow on aerodynamic performance. The engine-cooling channel was constructed at a simplified notchback model with various outlet layouts. The changes in the main aerodynamic coefficients with different cooling exit flow inclination angles and cooling outlet locations were measured and evaluated, and the reasons and mechanisms were analysed and discussed. The results indicate that reducing the inclination angle is an effective method to improve the cruise performance of a passenger vehicle, and wheels and wheel-housings have significant effects on interference between the underflow and the cooling exit flow.