Renault R26 technical insight

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The new V8 engines define the rear

With every car launch some changes can be expected while other surprise the world. While Renault won both championships in 2005, few enhancements could be found with competing teams, except maybe from McLaren.

However, the FIA set new engine regulations as they appeared to be driving costs of the teams. From 2006 on, only 90° V8 engines are allowed, except for teams that cannot afford such an engine at this time (Only Scuderia Torro Rosso is to use this possibility). The minimum weight has also been set to 95kg and the lifetime remains 2 full Grand Prix's for a single engine. Several well funded teams like McLaren, Ferrari and Toyota had already run an interim car equipped with a new V8 before new-year and saw the engine power initially drop to around 700bhp. Renault in the meantime, renowned for its well built engines focussed on developing the engine on the dyno. One must note that this is the only team that did not run a 90° V10 in 2005, but rather ran a 72° engine.

Together with the new qualifying format, the new V8 requires a smaller fuel tank because of higher fuel efficiency. It speaks for itself that this brings room to the engineers who design the in-car packaging of the car. The engine on its behalf also became shorter, dictating a focus on the rear end of the car. It proved to be the right choice in 2005 and many teams follow suit this year.

The previous illustration shows how much Renault has been focused to the rear end of the car. The rear wing has been bent up in the centre of the car (1) and is supported by a stabiliser in the middle. Since the air at the outer edges of the wing is cleaner and therefore more useful for downforce generation, more air is pushed over at the sides than in the middle of the wing. It is remarkable to see that only two years ago all teams went for the opposite approach by increasing the front area of the wing in the centre.

In an attempt to optimise airflow onto the rear wing and increase its efficiency, the sidepods have been made smaller but still resemble to those of the R25. As the new V8 engine requires less cooling, the air inlets are now smaller (4) and the shark gills that were very prominent on the R25 (see image on the right) were not needed at Jerez (3). Since temperatures were low at Jerez during the first test, it is not unlikely some gills will be present at the first race of the season in Bahrain. The closed sidepods allow for a smoother airflow over the pods instead of being mangled up with hot air. Renault seem to have done a really good job here, since other cars like the Red Bull and the BMW Sauber still require gills or big chimneys. Indeed the R26 has chimneys (2) but they are closed (for now).

An eye for detail

Since apparently all cooling areas have been closed, where is all that hot air going to? In its current specification, all that air is pushed out into and around the diffuser. A small channel (1) of carbon fibre has been made in order to do so at the highest possible speed. As visible in the image on the left, that channel passes under the pushrod of the rear wheel and separates the hot air from air flowing towards the centre of the car aside of the flipup.

Apart from engine rule changes, the FIA has also put some more weight into the rear impact test so that teams are obliged to incorporate a larger rear crash structure (2). Renault has chosen to do so by increasing the stiffness and length of the rear light attachment which is why now this car looks like having a small mouse tail (with some imagination).

Another detail not to be forgotten is the exhaust, located closely to the centre of the car and exactly in the edge of a bulge. The team has once again chosen not to extend the exhaust out of the chassis but wrap it into the car's body. It will therefore not hinder any air by means of an obstacle.

One final thing to note about the R26 is the sidepod air inlet. Renault has a peculiar design philosophy in this area as it rounds off the shapes that surround the air inlet. The McLaren MP4-20 or even the Ferrari F2006 have inlets that are very sharply cut, like designing the sidepod and then cut away what is not needed. Renault did it the other way in recent years with this design and appears to be satisfied by it.

More to come

As Renault have thought about every detail in the back, flipups have remained mainly the same as those of the R25 (that very aero package was only introduced 3 races before the end of the season). In front of the driver's helmet, little or nothing has changed at all. The car still used the V-keel suspension that was introduced with the Renault R25 and even displays the same front wing and nose cone. Initial testing of this car proved to be satisfying apart from little overheating problems at the back which were however quickly solved by simple heat covering. Just as with any other team, development is ongoing and I therefore expect updates to come even before the start of the season.

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