German car manufacturer, Audi has won the classic endurance race of the 24 Hours of Le Mans 11 times over the past 14 years. The Audi cars have always run faster despite the reductions of engine output due to the regulations.
Audi engineers worked hard to increase the aerodynamic efficiency of the LMP car.
With the innovative micro-tube radiator, Audi managed to make a major step ahead. The conventional aluminum louver-finned radiator that creates high aerodynamic drag is now a thing of the past.
The coolant in the R18 e-tron quattro flows through a system made up of more than 11,000 small tubes per radiator, and the radiators no longer require fins. These radiators can be freely configured. With the same radiator size, the pressure drop of the airflow can be reduced by more than 25 percent. Alternatively, with pressure conditions remaining the same, the size of the radiator can be reduced accordingly.
“The lap times reflect the significance of the strides that have been made in aerodynamics,” emphasizes Head of Audi Motorsport Dr. Wolfgang Ullrich.
“Of course there are many other influencing factors – the powertrain, the tires, the chassis, the ultra-lightweight design or the distribution of weight. To name just one example for the sake of comparison: In 2006, the fastest race lap at Le Mans was 3m 31.211s. The R10 TDI back then had 12 cylinders, 5.5 liters of displacement and, delivering more than 650 hp, was our most powerful LMP race car. Six years later, the best lap time was 3m 24.189s. Our cars had become more than seven seconds faster. But the V6 TDI engine of the Audi R18 ultra in 2012 was only allowed to have a displacement of 3.7 liters and delivered around 510 hp. A major share of these advances is owed to optimized aerodynamics. This year, we’re competing with a long-tail body that we expect to deliver further advantages for Le Mans,” Dr. Ullrich explained.
Audi engineers worked hard to increase the aerodynamic efficiency of the LMP car.
With the innovative micro-tube radiator, Audi managed to make a major step ahead. The conventional aluminum louver-finned radiator that creates high aerodynamic drag is now a thing of the past.
 |
| Photo: Audi Motorsport |
The coolant in the R18 e-tron quattro flows through a system made up of more than 11,000 small tubes per radiator, and the radiators no longer require fins. These radiators can be freely configured. With the same radiator size, the pressure drop of the airflow can be reduced by more than 25 percent. Alternatively, with pressure conditions remaining the same, the size of the radiator can be reduced accordingly.
“The lap times reflect the significance of the strides that have been made in aerodynamics,” emphasizes Head of Audi Motorsport Dr. Wolfgang Ullrich.
 |
| Photo: Audi Motorsport |
“Of course there are many other influencing factors – the powertrain, the tires, the chassis, the ultra-lightweight design or the distribution of weight. To name just one example for the sake of comparison: In 2006, the fastest race lap at Le Mans was 3m 31.211s. The R10 TDI back then had 12 cylinders, 5.5 liters of displacement and, delivering more than 650 hp, was our most powerful LMP race car. Six years later, the best lap time was 3m 24.189s. Our cars had become more than seven seconds faster. But the V6 TDI engine of the Audi R18 ultra in 2012 was only allowed to have a displacement of 3.7 liters and delivered around 510 hp. A major share of these advances is owed to optimized aerodynamics. This year, we’re competing with a long-tail body that we expect to deliver further advantages for Le Mans,” Dr. Ullrich explained.