Aerodynamic Forces Acting on a Race Car for Various Ground Clearances and Rake Angles


Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lučića 5, 10000 Zagreb, Croatia


Computational model was developed to investigate aerodynamic forces acting on a closed-wheel race car. A particular focus was on the effects of ground clearance and rake angle on aerodynamic drag and lift forces. Computations were performed for a steady viscous fluid flow using the realizable k-ε turbulence model and non-equilibrium wall functions. The computational results indicate a strong influence of ground clearance and rake angle on aerodynamic loading of a race car. The largest drag force coefficient was obtained for the largest ground clearance. The drag force coefficient for the squatting car is larger by 5% compared to the reference case, where the both front and rear ground clearances are 100 mm. For the nose-diving car, the drag force coefficient is equal to the reference case. Increasing the ground clearance caused a negligible increase in the lift force coefficient in comparison with the reference case. A decrease in the ground clearance yielded an increase in the lift force coefficient. The largest positive lift force coefficient was obtained for a squatting car, whereas the largest negative lift force coefficient was observed for a nose-diving car. While the favorable aerodynamic downforce acting on front wheels is larger for a nose-diving car, for rear wheels it is larger for a squatting car.