Experimental and Computational Modeling of the Aerodynamics of a Racecar 2001-01-2990

The aerodynamics of a typical Le Mans configuration is investigated numerically and experimentally. The purpose of the investigation has been to gain a better understanding of the aerodynamic characteristics of such configurations in extreme off-design conditions. Computational modeling is performed with a low-order panel method, while flow visualization is accomplished with dye injection in a water tunnel using a 1/24-scale model. At low angles of attack, excellent agreement is shown between the streamline patterns observed experimentally and those predicted computationally, despite the large differences in Reynolds numbers. Experimental results indicate presence of attached boundary layers over a large part of the car at very high angles of attack. Furthermore, strong vortical structures are detected around sharp edges of lower part of the car at these extreme attitudes. It is postulated that these flow characteristics assist the catastrophic departure of these vehicles once they separate from the track.