Experimental and analytical investigation of the effect of body kit used with saloon cars in Brunei Darussalam

The purpose of this paper is to study the effect of the aerodynamic forces on saloon car with and without the body kit. Two cars were selected for this project namely Nissan 350z and Mazda RX-8. Body kits of the manufacturer´s standard specification are used for the analysis. The aerodynamic analysis is made using wind tunnel equipment and also flow visualization is made to see the air flow profiles. From the experimental measurement, the stability of the car with and without body kit is discussed. Using Microsoft Excel, the functional relationship between drag coefficient (C_d) at zero degree angle of attack (α) and Reynolds number (Re) is determined. Using the above functional relationship, the Cd at other Re is found. Using above Cd and appropriate equation, energy loss due to drag and energy loss due to rolling resistance is found and discussed. Flow visualization is done to offer explanation for the results obtained from wind tunnel experiment.