The Audi R18 is developed by the Audi motorsport department and built sports car prototype in the 2011 version as the Audi R18 TDI, as well as in the years 2012 and 2013 as the Audi R18 e -tron quattro the 24 -hour race of Le Mans won.
R18 TDI ( 2011)
The R18 TDI is the use of cars by Audi for the 24- hour race at Le Mans and the Intercontinental Le Mans Cup 2011. Triggered by a rule change at Le Mans, the R18 TDI has received over its predecessor, the R15 TDI, some changes. Unusually for a closed Le Mans prototype, there is a monocoque made of one piece. The vehicle has, as required, a minimum weight of 900 kg. Also, the 6- speed gearbox is a new development from Audi. The Audi is the first time since 1999 - as beside the open Audi R8R the closed R8C was used - no roadster, but now as the Peugeot 908 a roof. This brings more aerodynamic efficiency. The main argument for a roadster, namely a faster driver change, fell away after the change in the sporting regulations, the Pitstopps now last a lot longer. The characteristic fin is due to the regulations, at turners here is the air resistance absorb the energy. The Audi R18 TDI is the first time in the history of Le Mans, a completely equipped with LED lighting technology vehicle at the start.
The vehicle was unveiled to the public in Ingolstadt on 10 December 2010 and gave its race debut at the 1000 km of Spa -Francorchamps in May 2011, while in third place behind two Peugeot.
Rider line at the 24 - hour race at Le Mans 2011
In the Audi No. 1 sat the last year's winner Timo Bernhard, Romain Dumas and Mike Rockenfeller. The second team made the Swiss Marcel Fässler, the German André Lotterer and the Frenchman Benoît Treluyer. The Audi with starting number 3 piloted the experienced trio Tom Kristensen, Rinaldo Capello and Allan McNish. The vehicle with the number 3 fell after a collision with McNish at the wheel, made in the first hour of the race. Also, the vehicle with the number 1, piloted by Mike Rockenfeller, was completely destroyed after a collision with a Ferrari. The number 2 with Fässler, Lotterer and Tréluyer could win the last remaining vehicle the race just ahead of three Peugeot 908, which means the 10th overall victory at the classic endurance race for Audi Motorsport.
R18 ultra (2012 )
The R18 is the ultra extensively revised edition of the R18 TDI for use in the 24 - hour race at Le Mans in 2012 and for the new FIA FIA World Endurance Championship. Externally the new model remained without noticeable changes. Motor side, a 3.7-liter V6 TDI unit is still used. Strikingly, however, is the unique turbocharger concept. It is around a central exhaust gas turbocharger arranged directly between the classical V-shaped 6-cylinder diesel engine. Since the exhaust manifold are also directed inwards, an extremely short exhaust path results to the exhaust gas turbocharger, whereby the energy losses are minimized. Another advantage over the conventional Bi-Turbo version with two turbochargers is that only one, but larger turbine is used, which has a slightly higher efficiency result, since eg the loss of a large gap loader versus two smaller ones is reduced overall. The turbine side of the turbocharger has two radial inlets and an axial outlet and the compressor side of an axial inlet and distributes the air after compression evenly to the two cylinder banks. Further, the turbine operates with variable turbine geometry, which allows to operate the turbocharger optimally depending on the load state.
R18 e -tron quattro (2012 and 2013)
The R18 e-tron quattro is a model of R18 ultra with hybrid drive. With the revision to R18 Ultra also two different, interchangeable drive versions were designed. The chassis of the R18 e -tron quattro is completely identical with that of the R18 ultra, but has in addition to the conventional rear-wheel drive of the R18 ultra means of diesel engine, a hybrid system in the engine compartment and a switchable front-wheel drive by electric motor / generator units called regenerative braking part of the braking energy can recover as electricity. In addition, the R18 e -tron has additionally a flywheel or Gyrospeicher for short-term, temporary storage of kinetic braking energy.
At the 24 Hours of Le Mans 2012 Audi gained a triple victory, with the top two spots were occupied by the two being beaten Audi R18 e-tron quattro. Thus, for the first time won a hybrid vehicle this race.
For the 2013 season a number of modifications to the car were made, so the car now has double end plates at the rear, as they are also used on Toyota TS030 Hybrid, this increase downforce on the rear axle. Also on the front aerodynamic changes were made. For this purpose, the hybrid system has been significantly improved, the recuperation is now more efficient by 15 to 20 percent instead. Thus, the full power of the hybrid system is now also available by curves with short braking phases.
The engine is now a 3.7- liter V6 engine (540 hp) is indicated with an output of over 397 kW. Experts estimate the performance to about 470 kW. Audi used for the drive but again on the diesel technology. Compared with the previous V10 turbocharger was moved to the top, just like the exhaust side. This will also get higher aerodynamic efficiency together with the smaller engine. In addition, the exhaust gases and the cooling air can escape so that they interfere now less airflow around the car. According to the audio engine is easier also by 25%. The engine would have under these rules can also be a V8, but Audi wants so exhaust the reduction even further.
R18 e -tron quattro (2014)
The 2014er version of the Audi R18 is actually a completely new car which was developed for the new, as of 2014, current LMP1 regulations. The engine is a further developed V6 TDI from its predecessor, with 30 % less consumption. It was originally planned to connect the turbocharger with the hybrid system, it was here now to an e- turbocharger. He produced electrical energy when the charge pressure limit was reached. This then flowed into the rotating mass storage, which is also fed by a KERS on the front axle. Depending on the operating strategy for accelerating the stored energy could be released back into the front axle or the turbocharger. The E- Loader part of the hybrid system but was rejected for reliability reasons. The other changes relate, inter alia, a narrower by 10 cm body, narrower tires, an increase of 1,050 mm Vehicle height, a front wing with flaps instead of a front diffuser, wider by 20 cm rear wing, a reduced gross weight of 870 kg ( net weight: 760 kg ) Tethers for the front wheels, a Crasher behind the transmission which absorbs the energy in an accident, a reinforced monocoque and a modified exhaust system, a sequential seven -speed gearbox. In the, according to Audi, the most complex race cars the brand has ever built, each component has been newly developed.