Investigating Changes to the Downforce Curve of a Double Element Airfoil in Ground Effect 2004-01-3558
As part of on-going research into ground effect aerodynamics at the University of Southampton, attempts have been made to shed light on variables that may influence the characteristic shape of a typical multi element airfoil downforce curve while varying ride height. To achieve the stated goal, a commercial CFD software package was used to perform a comparative aerodynamic analysis study.
The height of a double element airfoil above the ground was varied, while the values of lift and drag obtained were recorded to provide baseline information. The angle of attack of the flap and the main element were then changed in order to discern any effects on the lift curve. Also investigated was the effect that the relative sizes of the main element and flap had on the lift and drag curves, since modern racing car wings vary in this manner across their span.
Analysis of the resulting data showed that in the case of the double element airfoil, increasing the angle of attack of the main element reduced the downforce sensitivity. Additionally, as this angle was increased, the maximum downforce generated by the airfoil was reduced. Increasing the size of the flap element relative the main element, at constant airfoil chord, had the effect of reducing the ride height at which maximum downforce was attained.