an interesting article on why the Red Bull exhaust design continues to favor Vettel
(translated from German).
Formula 1 exhaust comparison 2013: Red Bull continues to rely on Vettel exhaust
The exhaust is a popular playground for the engineers. The teams have agreed on two different concepts. The Red Bull solution has only been followed Lotus. Among the McLaren-trailers there are plenty of ways to play. We show you the options and explain the pros and cons.
Since Red Bull designer Adrian Newey has chosen to exhaust the favorite toy, also his colleagues plunge it. 2011, the exhaust gases controlled at rear with up to 25 percent of the output. Then the tailpipes were still in the bottom plate and just before the column resulted between the diffuser and the rear wheel. And the engine could also produce exhaust gases during towing.
The exhaust jet was abused to the diffuser side seal. Why is this so important? Because you so you could lift the car back. The diffuser at the rear end may not only 125 mm above the reference plane. You put on the car, the distance to the road. The trick therefore creates a larger diffuser expansion. But only works if no air can flow laterally. You need the exhaust gases. They work like side skirts.
Exhaust must aim precisely
The principle works for the big exhaust restriction 2012 still, just not as good. The regulations stipulate the tailpipes before a rectangle, in which they must lead. And that is much further away from the destination than in 2011. There is therefore a risk that the scatter gases and heat the rear tires. In addition, the exhaust tips have at least ten degrees upward angling.
As did the engineers utilize the Coanda effect. Following this physical principle, a flow always follows a surface, while this area is not too sharp curves has. Crucial is the profile of the shaft in which the exhaust stream about 20 inches long. They come with a strong twist of the tail pipes. Who installs behind too many edges and corners, makes for a strong scattering. Throughout the 2012 season developed two approaches to bring the exhaust gases to where they are to perform their duties.
Better bottleneck effect at McLaren
First there would be the McLaren
Principle. Here, the tail pipes embedded in a bulge at the rear part of the box side and blow obliquely downwards or even just to the diffuser column. Since the bulge is only in the upper region of the side parts, one can move the panel below the usual a bottleneck.
The tapering of the engine cover takes to force the air to the side panel along the free surface above the diffuser. The more open space in the rear wheels, the better the Absaugeffekt works under the car. The rising part of the underbody is there, the air under the vehicle to suck so that the flow rate is not reduced by the friction of the air with the street and the floor.
Red Bull exhaust unerring
Red Bull and Sauber 2012 presented a different idea. You have put a dent in the tailpipes, which was admitted into the flat expiring sidepods. Behind the exhaust outlet or the lining followed as a ramp up to the base plate. This has caused a higher accuracy, because the exhaust gases could swirl in open air. The downside is that the ramp is an early collection of side boxes in the way. This reduces the beneficial effect of the bottleneck.
Since Red Bull designer Adrian Newey resorted to a trick. He punched near the bottom two holes in the side parts, through which he sucks the lateral flow into the interior. The air then passes over and under the diffuser again. This partly compensates for the loss by the diluted bottleneck shape. Adrian Newey is of course a step further. Over the winter, he shortened the ramp by making it steeper. Thanks to a shortened sidepods can RB9 the back as you move earlier than the old RB8.
Red Bull for better acceleration, braking McLaren
The two concepts have a massive effect on the driving behavior. In fast corners the differences are minimal. But when the load changes the handling characteristics change depending on exhaust concept. Ross Brawn said: "The Red Bull is a better solution for acceleration, because the exhaust gases more accurately and quickly get to the destination, if the driver is on the gas, he will feel the effect accordingly better.."
"The McLaren system has advantages when decelerating. Reduced, since the intensity of the exhaust jet. Influence on the pressure goes back so. Therefore, the bottleneck and the natural flow exert their function fully. And because that is pronounced in the Red Bull less There are problems with the braking stability. "
That is also the reason why Sauber has strayed from its own idea again and the McLaren Group has connected. The biggest problem the Sauber of 2012 was instability on corner entry. Therefore copied Lotus
the Red Bull exhaust. This is believed to have the disadvantages under control and to benefit from the better traction.
Red Bull exhaust suits Vettel driving style
Malicious will claim Red Bull have built a Vettel-exhaust. Red Bulls exhaust solution helps on corner exit, where Mark Webber is stronger. The Australian thus benefits from the advantages of minimally. He suffers more from a nervous driving into corners than Vettel. This was also one of the reasons why Webber was in the first half of 2012 season so strongly. Since Red Bull had his exhaust system has not been perfected. The decisive step forward was made in Valencia. And as for the pendulum swung towards Vettel.
That Webber has won at Silverstone, does not refute the thesis. Silverstone is the track on which the least is slowed. Therefore, the deficits were there also revealed little. In fairness it must be said that Newey has worked on the missing braking stability. This is supported by the shortened sidepods and the channels that start even earlier. Both supports the neck feature.
Ferrari presents interim solution
Among the brethren of McLaren, there are many ways to play. The model now entirely dispensed on a bump in the sidepods. The bay where the tailpipes are running out of the bottom plate. Ferrari
is because the most extreme way. The engineer troops of Pat Fry warmed in testing the first exhaust solution from 2012 to again. It is the bulge in the side box to type trunk.
So will give Ferrari the tailpipes into the diffuser column next possible position. Further out, further down and further back does not work. Last year failed the test because the rear tires were too hot. Obviously makes the second start-up problems. On the third day of testing we saw already a more civil version of this variety.
Mercedes, Force India and Marussia have presented an offshoot of it. However, there is a difference. At Mercedes
and Force India is the trunk in the back again over the cowling. Ferrari and Marussia open the bump behind the exhaust and leave it there, the hot air emanating from the radiators.
We show in our gallery again exhaust all options in detail and explain the pros and cons.