Computational fluid dynamics simulations of a Formula Student race car - Effects predicted by the modelling of a steady state cornering vehicle
Abstract
In this thesis work an investigation of the aerodynamics of a Fomula Student race carwas conducted. The work focused on a computational fuid dynamics evaluation of theaerodynamic effects predicted for the car moving through relatively sharp corners ofconstant curvature. To assess the credibility of the closure models investigated, comparisonswith experimental reference cases were conducted. To put some bounds on thenumerical discretization errors for the car simulations, a grid convergence study was alsoconducted. For the simplied wing validation test cases, a relatively good agreementbetween aerodynamic performance values obtained from experiments and simulationswas found. For the full car simulations, comparisons were made with on track measuredvalues of lift. With respect to the measured values, the predictions of lift obtained fromthe simplified computer model geometry was high. It is believed that this was due, inpart, to the simplicity of the model geometry, allowing for less disturbed air flow around the lift generating devices of the car, as well as the turbulence models inability to accurately predict amplitudes and the stream wise extent of the wake of bluff bodies directly upstream of several key lift generating devices. For assessing the aerodynamic effects of steady state cornering for the vehicle the momenta about its yaw, pitch and roll axes were tracked. In addition, lift, drag and sideforces were investigated. The modelling of rotational flow around the car found effects not present in, and in direct opposition to those predicted by modelling a cornering vehicle as having a fixed yaw angle with respect to the free stream.