CFD-analysis of the aerodynamic properties of a Mercedes-Benz 300SLR

Abstract

Mercedes-Benz was one of the most prominent car manufacturers in motorsport in the 50’s. In 1955 they participated with the model 300 SLR in the Le Mans 24- hour race. What made this model standing out was the mounted air brake, which would compensate for the weaker drum brakes compared with competing models’ disc brakes. During the ongoing race the world became witness to one of the most fatal accident in motorsport history, where the Mercedes in a collision flew up and crashed into the grandstand. The aim of this work was to investigate the air brake’s effect on the car’s characteristics at the crash moment. This is done by monitoring the work of Peter Gullberg and Lennart Löfdahl performed in 2008, but with a more accurate basis. A laser scanned model of the car that was obtained from Gullbergs and Löfdahl’s work in 2008 was improved to match more with the real car and to obtain accurate results in the flow simulations performed in STAR CCM+. The results obtained confirmed the earlier work in the field which indicated that the car gets an overall higher downforce with the air brake engaged compared to the down position. Additionally, a major downforce was noted on the rear axle compared to the front when the air brake was engaged.