Experimental investigations on aerodynamic characteristics of a hatchback model car using base bleed

Wind tunnel tests have been conducted on a realistic hatch back car model, to investigate drag reduction opportunities from injecting low velocity air into the base region. Various techniques to reduce the aerodynamic drag of bluff bodies through the mechanism of base pressure recovery have been investigated. The investigation is conducted in free stream and in ground proximity. It is shown that, with a base bleed hose, the overall body drag is reduced. The paper shows the method used in creating the scaled model of the car and conducting the analysis, and presents the findings to date. The paper shows that the reduction in drag increases as the mass flow rate of air is increased when the flow is deflected at the outlet. By controlling the turbulent wake to the rear of the vehicle. It has been shown that base bleed can significantly decrease drag when applied to the geometry of a real hatch back model car, For the geometry studied, a bleed outlet applied to the lower portion is most effective in reducing drag. Thus the reduction in drag improves the fuel economy. The paper also discusses the feasibility of base bleed being applied to a production vehicle.