Red Bull RB8 Renault

[marcush.]

I think the tunnel thingy does help Webber only when Vettel seem to have difficulty to exploit the potential.
So will they have to develop in two directions for the rest of the season?

It looks more and more like all the exhaust coanda thingies do not really net enough performance for the effort you are investing..that´s sidepod config no ?? and still not the solution...

[Greenish]

Yes thx, cant jsut be me seeing 2 streaks?

It could be during the fast parts of the track heat the lower area, and during the slower ones heat the higher area were the exhaust really aim.

I would expect there to be a vortex shed from each side of the 'tunnel,' since there is different pressure inside and outside of it. If those two vortices take different paths then they could cause two streaks.

Or it could be lighting and there is more curvature in those spots and there is a specular reflection.

[bhall]

I think the tunnel thingy does help Webber only when Vettel seem to have difficulty to exploit the potential.
So will they have to develop in two directions for the rest of the season?

It looks more and more like all the exhaust coanda thingies do not really net enough performance for the effort you are investing..that´s sidepod config no ?? and still not the solution...

I don't think their "tunnel" exhaust works, at least not the way they want it to. The aim of that configuration is to seal the diffuser by using the much-vaunted Coanda effect to direct air flow around the chassis through the "tunnels" so that it doesn't diffuse the exhaust plume before it gets to the edge of the diffuser.

The problem, I think, is that it only works while the driver is on the throttle, and even then it's likely nowhere near as effective as anything seen on last year's cars. So, what you've got then is, essentially, a system that destabilizes the car while adding a little benefit.

As we've all seen over the years, Webber is much better than Vettel with iffy balance. Hence their relative performance in qualifying today. Vettel is pretty much handicapped by the fact that, for whatever reason, he can't drive around the "tunnel" system's instability. That's why he doesn't use it.

Keep an eye on Red Bull's exhaust in the coming races. If my assumption about Ferrari's new exhaust chamber is correct in that it helps to stabilize the transition between a driver being on the throttle and off, I expect to see it adopted by those teams that are going back and forth between different exhaust layouts.

[raymondu999]

I think the tunnel thingy does help Webber only when Vettel seem to have difficulty to exploit the potential.
So will they have to develop in two directions for the rest of the season?

It looks more and more like all the exhaust coanda thingies do not really net enough performance for the effort you are investing..that´s sidepod config no ?? and still not the solution...

The tunnel isn't really a characteristic problem in terms of driving IMO. It's that the tunnel is choking - an aero, technical problem. CFD and windtunnel is saying that the tunnel should work and feed the coke bottle, but track is showing the tunnel chokes. Both drivers are faster with no tunnel. (see Bahrain)

I don't think their "tunnel" exhaust works, at least not the way they want it to. The aim of that configuration is to seal the diffuser by using the much-vaunted Coanda effect to direct air flow around the chassis through the "tunnels" so that it doesn't diffuse the exhaust plume before it gets to the edge of the diffuser.

You're confusing 2 things - the tunnel is a system to get the sidepod undercut flow into the coke bottle region, while the coanda exhaust directs the air just over the top over the sidepods.

See here: http://scarbsf1.wordpress.com/2012/04/2 ... -analysis/

The problem, I think, is that it only works while the driver is on the throttle, and even then it's likely nowhere near as effective as anything seen on last year's cars. So, what you've got then is, essentially, a system that destabilizes the car while adding a little benefit.

Thing is same can be said about every non-neutral exhaust setup. Such as the McLaren one.

As we've all seen over the years, Webber is much better than Vettel with iffy balance. Hence their relative performance in qualifying today. Vettel is pretty much handicapped by the fact that, for whatever reason, he can't drive around the "tunnel" system's instability. That's why he doesn't use it.

Neither did Webber AFAIK. I think it's not that Webber is better with iffy balance - but rather both deal better with opposing imbalances. Webber seems to handle understeer better, Vettel seems to handle oversteer better. Oftentimes we see them both running with cars that can be quite different - Webber with a bit more understeer, Vettel with a bit more oversteer.

A big part of the current balance in power between the two drivers IMO is the lack of off-throttle blowing. Since China 2010 Webber has always better managed a car that is throttle-sensitive in terms of downforce. See here: http://news.bbc.co.uk/sport2/hi/motorsp ... 127533.stm

In its initial form, this component required a very specific driving technique to maximise the time on open throttle - which increased the downforce boost from the exhaust plume - and Webber was superb at it, consistently squeezing just that little bit more from it than his team-mate.
Vettel continued to be better at living with a little bit of entry oversteer, and that ability to adapt to the car moving around him was maybe partly why he was not as insistent on adapting his technique to a feature that calmed the rear end as soon as you got on the throttle.

[bhall]

You're confusing 2 things - the tunnel is a system to get the sidepod undercut flow into the coke bottle region, while the coanda exhaust directs the air just over the top over the sidepods.

See here: http://scarbsf1.wordpress.com/2012/04/2 ... -analysis/

The Coanda effect is not limited to the exhaust plume traveling down the "bridge." The very same effect accounts for air flow around the side pods sticking to them and getting to the "Coke bottle" area to which you refer. The "tunnels," which are just extremely undercut side pods, give the air flowing around the side pods, which is ostensibly attached to them because of the Coanda effect, somewhere to go that won't interfere with the exhaust plume moving down the "bridge" over the "tunnels". Otherwise the exhaust plume would be annihilated by that air flow before it can reach the edge of the diffuser to seal it off.

And, you're right. Because this solution is dependent upon exhaust to work, its effectiveness is hampered by the relative lack of off-throttle exhaust blowing this year. That's something every team striving for exhaust downforce at the diffuser has had to address.

The team is also hampered by the fact that the regulations only allow 50mm above the floor for the "tunnel." Apparently, they need more room, or something else, to keep it from choking. I think that's why Ferrari went down a path that sought the same end, but with exhaust arms to inject the plume rather than a bridge and tunnel system to guide it. (Not that it did any good, mind you.)

For whatever reason, it seems Webber can make this system work better than Vettel, even though it can lead to snap-oversteer when the driver lifts the throttle. I don't have an answer for that. It's just apparent.

Like I said, keep an eye out for that Ferrari exhaust chamber. I suspect it's coming to a Red Bull near you.

[raymondu999]

No that's what I'm saying with the off-throttle sensitivity. It can be set up to have oversteer off throttle, stable on throttle, or stable off throttle and understeer on throttle, or somewhere in between. I think Webber sets it up for stable off throttle, then uses the exhaust downforce as added stability and traction.

Apologies for not making my words clearer.

I think RBR should take it on the chin, admit McLaren did a better job, and smack on the McLaren sidepod style exhausts, then focus on the more fundamental aerodynamic package of the car.

[bhall]

Though I don't necessarily see it that way, I see your point.

The "bridge" exhaust gives more total downforce - because it seals the diffuser - but at a cost of some stability - because it's throttle-dependent. If a driver can cope with the instability, however, this solution will be quicker outright due to the added downforce.

On the other hand, the "non-bridge" exhaust sacrifices downforce in favor of stability. This makes it somewhat slower than the other solution - because it doesn't seal the diffuser - but it also makes it easier to drive - it's less dependent on the throttle.

While that solution will not inherently be as quick as the former, it could prove to be as quick or quicker over the course of a race due to the car being easier to drive on the limit without mistakes. But, if Webber doesn't make any mistakes, he will be faster.

We'll see how it all works out tomorrow (today?).

EDIT: I definitely agree with you that Red Bull should probably drop the "bridge" exhaust, even though it has more potential. I just think the resources needed to make it work in-season would be better spent elsewhere and likely for bigger gains. I think these systems will work next year, though. They need off-season-type devotion. (Because of that, they should be given a woman's name.)

[Teechnical]

So wait, the Ferrari's simple exhaust solution is better than the Redbull's bridge ones? Or rather works more effectively?

EDIT: I know the bridge ones have a lot o potential, but i dont think its being used to the max, so they should drop it.

[bhall]

I'd say it probably works more predictably. Of course, there's no way to be sure, and predictable doesn't always equate to better.

EDIT: I should say that all of this is predicated on the notion that Red Bull isn't dealing with a lot of complementary issues.

[Gridlock]

Tunnels on the mind, understandable this weekend I guess

Race 6, time to settle on a configuration and work with it? RB8 in danger of falling behind those who have?

[dxpetrov]

I guess it's very marginal, with or w/out it... So they are not losing on anything. Less so than McLaren, who actually have worse race pace than RB.

[Gridlock]

A flurry of tweets and Andrew Benson suggesting VMM, MB and SFM are to protest the RB "floor" - starter motor hole? Pre-wheel slots?

[bhall]

VMM?

[Gridlock]

Sorry, am slipping into Peter Windsor mode, Vodafone McLaren Mercedes

According to the Monaco race thread this protest is happening, as in, these teams are in with the FIA right now (TV3 quoted as source). Scarbs is on it on twitter.

[ESPImperium]

Looking at a couple pics that Crucial_Extreme posted, im thinking there could be a new DDD controversy.

If you look at the slit that is under the exhaust, it seems to go no where, im thinking there could be a channel into the centre section that you can do anything with, as in that area you can push air into and get free downforce. However it in my opinion dosnt infringe on any rules that are there to stop DDDs as they were in the first incarnation in 2009/2010.

Just my 0.02p of analysis.

Im looking at this pic BTW: