Audi has produced two versions of its LMP1 car, the R18 e-tron quattro. The second body version of the R18 made its debut at Spa and features a bodywork that produces less drag for the Le Mans high-speed circuit.
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| Audi R18 e-tron quattro, high downforce version (Photo: Audi Motorsport) |
“Using multiple simulations, we try to clarify even before the first test whether or not the car generates sufficient downforce to achieve the desired cornering speeds. At the same time, it is necessary to prevent excessive aerodynamic drag because we have to be fast on the straights as well,” said Dr. Martin Mühlmeier, Head of Technology at Audi Sport.
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| Audi R18 e-tron quattro, low drag version (Photo: Audi Motorsport) |
For this reason, Audi has developed two variants: one body version with minimal aerodynamic drag for Le Mans and one for the other seven World Endurance Championship tracks that require higher downforce.
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| Audi R18 e-tron quattro, high downforce version (Photo: Audi Motorsport) |
Even at first glance, the two body versions clearly differ from each other, as could be seen during their joint fielding at Spa.
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| Audi R18 e-tron quattro, low drag version (Photo: Audi Motorsport) |
“Nearly all the relevant areas of the bodywork have been optimized,” explains Jan Monchaux, Head of Aerodynamics at Audi Sport.
“At the front, the modified fenders with openings on the inside instead of at the top are noticeable. The differences at the rear are conspicuous. The body is now flush with the rear wing and fully uses the maximum length of 4,650 millimeters. By contrast, the high-downforce version has a shortened body. The tailpipes differ as well. For Le Mans, they do not exit to the right and left of the central fin but at the body surface above the diffusor,” Monchaux explained.
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| Audi R18 e-tron quattro, high downforce version (Photo: Audi Motorsport) |
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| Audi R18 e-tron quattro, low drag version (Photo: Audi Motorsport) |
