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The 2016 Audi R18 racecar features a more radical aerodynamics concept including a new safety cell, its hybrid drive system is battery-operated for the first time, its V6 TDI engine has been revised, and new system solutions have been added. As a result, Audi’s LMP1 sports car is a vehicle that is more powerful and yet clearly more efficient than its predecessor. While the new R18 is Audi’s strongest racecar to date, it consumes less fuel than any of the generations before it.
Power output of more than 1000bhp delivered by the TDI and hybrid powertrain is accompanied by 10 percent less fuel consumption than before. The FIA WEC regulations have been providing automobile manufacturers with incentives to build increasingly efficient racecars since 2014. Starting in the 2016 season, this competition will intensify, as the upper limit for fuel consumption will considerably decrease by 10 megajoules per lap at Le Mans.
All development engineers at Audi Sport were challenged to enhance the efficiency of the Audi R18. As a result of switching to the 6-megajoule class, the hybrid system, due to the regulations, now recovers 50 percent more energy. At the same time, the car’s aerodynamics concept is fundamentally new, with nearly all vehicle systems refined or redesigned. Consequently, energy consumption decreases, the race car has become lighter, thereby allowing for more favourable packaging of the component assemblies. This has resulted in an R18 which, even visually, clearly differs from its predecessor.
No other modern racecar embodies the philosophy of optimised aerodynamics as consistently as the LMP1 sports cars that render a futuristic impression. When looking at the new Audi R18, a significantly altered exterior strikes the eye. The proportions of the front end and the cabin within the overall vehicle length have changed, and the conspicuous nose of the racecar is clearly slimmer than before.
New as well are the dimensions and positions of the prescribed openings in the front wheel arches. They are intended to reduce undesirable aerodynamic lift effects in the case of lateral airflow. Their areas have been enlarged by 45 percent compared with the 2015 season.
This new concept requires innovations in many other areas. The suspension is a case in point. The transmission is a new design as well. Audi’s simulations revealed that the optimised engine allows a very good gear ratio spread with minimal rpm jumps, even in combination with a 6-speed instead of the previous 7-speed unit. As a result, the engineers managed to further reduce the weight of the transmission.
In the other areas of the vehicle’s structure, Audi rigorously pursued its lightweight design approach as well, while retaining the high torsional stiffness of the chassis. In addition, new solutions for the actuators of the R18’s individual systems help reduce weight. The regulations prescribe a minimum weight of 875kg for the LMP1 hybrid sports cars. In spite of a more powerful and therefore necessarily heavier hybrid system, Audi does not exceed this limit.
Hybrid pioneer Audi, the first manufacturer to have won the Le Mans 24 Hours with an energy recuperation system, was using a flywheel energy storage system from 2012 to 2015. Now the time is ripe for the next step – electrokinetic technology is being replaced by an electrochemical storage system.
The previous flywheel accumulator guaranteed high power density. Now, favourable energy density has to be achieved as well, as Audi is switching to a higher hybrid energy class. Starting in the 2016 season, the amount of energy will increase by 50 percent to 6 megajoules. When comparing this level with the one from the 2014 season, the engineers have even tripled the amount of recuperated energy within this period of time.
Be it in terms of the performance capabilities and safety of the racecars or the furthering of efficiency and innovations, in the sum of all technological features, the LMP1 class remains unique around the globe and therefore of utmost relevance for the future of the automobile.
(Click here to read about our experience at the 12-hour Malaysia Merdeka Endurance Race at Sepang.)
(Click here to read our review of the R18’s street-legal relative, the second-generation R8.)
