Influence of Base Slant on the Wake Structure and Drag of Road Vehicles

Abstract

The time averaged wake structure of a realistically dimensioned quarter scale automobile model was studied in a wind tunnel on the basis of flow visualization, wake surveys, force and pressure measurements. Through a systematic variation of base slant angle in the range of 0 to 40 deg, the ensuing changes in the wake structure were observed and the wake structure present at lowest value of aerodynamic drag is shown. Experimental data were obtained at a model length based Reynolds number of 4.29 million. Correlation of wake structure with drag, pressure distribution, and kinetic energy content of vortex motion in wake is addressed.