FUEL ECONOMY ENHANCEMENT OF AN SUV BY AERODYNAMIC DRAG REDUCTION USING ADD-ON DEVICE SPOILER WITH VALIDATION ON 1:5 REDUCED SCALE MODEL

摘要

Flow structure in the wake region is most critical parameter for vehicle aerodynamics. For an SUV its dominated by downwash and secondary three-dimensional vortices associated with it, which creates lower pressure at the rear that increases the aerodynamic drag. This paper presents a study on drag reduction by controlling the flow in the wake region using add-on device 'Spoiler'. In this work firstly baseline full scale model of an SUV is investigated numerically in virtual wind tunnel and then a 'Spoiler' has been investigated for drag reduction. As a proof of concept 1:5, 3D printed reduced scale model with and without spoiler has been tested in wind tunnel. In this work drag reduction has been observed in full scale simulation and reduced scale wind tunnel testing also. An approach has been presented in this study for validating various concept for aerodynamic improvement using reduced scale model wind tunnel testing. In this paper scaled model wind tunnel testing and simulation has been compared to have better understanding of flow structure and validation of CFD methodology, around 97% correlation has been observed in force measurements. Further this paper discusses about relation between Fuel economy and aerodynamic forces acting on vehicle. In present work using engine power consumption equation fuel economy improvement of 2.04% has been obtained theoretically with add-on device 'spoiler'.