An investigation into the aerodynamics of a wing in ground effect in generic racing car wake flows

Wind tunnel experiments and CFD simulations were carried out in an attempt to shed light on the aerodynamic changes that a leading open-wheel racing car would induce on a following car of similar specifications. The leading care was idealised as a bluff body that was equipped with a rear wing and a diffuser, while the following car was represented by a front wing that was located further downstream. The tests entailed varying the height and angle of attack of the front wing above a moving ground, while changing the oncoming flow conditions. The oncoming conditions were generated by a stand alone rear wing, the bluff body with different diffuser angles and the bluff body at different heights. The results from these cases were compared to the results obtained from the undistributed freestream. Data collection methods included force and pressure measurements, in conjunction with flow visualisation images from the surface of the wing. Velocity flow field measurements were taken with PIV and LDA. The investigations showed that the wing experienced a decrease in downforce when downstream of the idealised leading car. The decrease was found to vary with the height of the wing above the ground. The investigations also showed that the wing experienced an increase in drag at the downstream location, and that its efficiency increased as the diffuser angle was decreased. The aerodynamic changes were linked to the flow field generated by the upstream configurations.