Red Bull RB9 Renault

A place to discuss the characteristics of the cars in Formula One, both current as well as historical. Laptimes, driver worshipping and team chatter do not belong here.
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Holm86
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Re: Red Bull RB9 Renault

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Thunders wrote:you mean from this Preview ?

https://pbs.twimg.com/media/BaEkQqWCUAAEL-8.jpg

Edit: The Preview Text on the sportbild HP mentions a Duck Nose, whatever this will be. ^^

I'm sure the Full Pic will find it's way to the Internet. ^^
Looks like there is an s-duct. But those sidepods looks a bit tight taking the new crash structures in consideration.

trinidefender
trinidefender
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Re: Red Bull RB9 Renault

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I actually find it quite funny how some people here talk about the designers of various F1 cars like they are 8 year olds racing box carts with planks for wings down hills.

@Ringo - the concept of using large radiuses (yes that is a correct form of the plural of radius, another being radii) is a fairly well understood concept in aerodynamics. It is nothing like trying to use blown exhaust gases which is still not known all that well, I'm sure if you have teams a few more years using the current rules you'll see teams get faster and faster every year and beating the times set by this years rb9. If you look at petty much every aircraft design you will see see smooth wide curves almost everywhere you look. I am pretty sure F1 aerodynamicists understand this concept just as well. In fact if you compare a feature on the rb9 and f2012 you will notice something. At the top of the sidepods of the rb9 there is quite a steep drop off behind the vortex generators going backwards toward the exhaust area. On the f2012 the same dropoff has a much smoother radius. You would think this would be better but the truth is, on that part of the car none of us really know, all we can do is speculate. Also we don't know exactly what the air is doing on either car before it hits the top of the front of the sidepods which will also have an effect of how the sidepods are shaped. Ringo my point is, these guys and girls designing the cars are not idiots, don't treat them as such, pretty much all did some form aero education at university and would have gone over this.

Personally I think the reason they can run smaller wing angles than other teams is because they can run so much more rake than other teams. From that my next question would be how do they run so much rake.

Another personal opinion of mine is that I think Sauber has one of the best designs when it comes to reducing lift over the top oft heir sidepods. How it is sloped down to the side as well as sloping back instead of just sloping back probably allows the higher pressure air to mix in better reducing the low pressure air above the sidepod and reducing positive lift therefore requiring less negative lift (downforce) from wings/diffusers to counter it. That is why I think they have had a good car later on in the season even on such a small budget.

Owen.C93
Owen.C93
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Re: Red Bull RB9 Renault

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Kiril Varbanov wrote: @Owen - Certainly, you are right, the inlet shape and size has a huge effect - both on shape drag and internal drag coefficients. Check World War II stories about radiators. Or just any aero book.

Final words from me on RB9 - excellent job Newey and team. See you in 2014.
Yeah. Specifically using the rads like a RAM jet to produce thrust (or less drag). Which is probably why you'll see the RBR cooling outlet aimed at the beamwing and never through gills.
Motorsport Graduate in search of team experience ;)

trinidefender
trinidefender
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Re: Red Bull RB9 Renault

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@Owen.C93 I think what you are referring to is the Meredith effect. See here http://en.wikipedia.org/wiki/Meredith_effect . I was looking at the exact same thing actually. I actually think the f2012 uses the effect with the radiator cooling exits next to the coanda exhaust exits. When I was doing some research on it, I noticed that designers placed the radiators more or less inline with the exits to minimise energy lost. However the way how RedBull exit looks always made me think of many of the WWII radiator designs that used the Meredith effect to produce thrust that counters the drag created by the radiators themselves.

eyalynf1
eyalynf1
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Re: Red Bull RB9 Renault

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I also think there is more to the RB9 aero advantage than radii, although this is certainly a contributor to good aero performance and efficiency. Particularly at the yaw angles caused by cornering and wind.

I was doing some reading and I noticed that the longitudinal cross section (long axis) of the side pods, if cut at various angles, reminds me of a relatively symmetrical airfoil section. Specifically, an airfoil section designed for inverted flight where the sign of the lift depends on the angle of attack. Optimizing this overall shape in this way could be the source of counteraction to the lift discussed earlier.

Edit - actually, the cross sections aren't symmetrical, they are asymmetrical with the curved surface on the bottom and flat on top, so more dedicated to providing negative lift if the governing equations are integrated across the surface of the sidepods!

And the final touch - the previously discussed vortex rooted from the front wing edge travels in "Ringo's Radius" to enhance the low pressure along the underside of the side pod.

eyalynf1
eyalynf1
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Re: Red Bull RB9 Renault

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Huntresa wrote:
siskue2005 wrote:http://i.imgur.com/Mkshjgy.gif
Is the vortex bouncing off the barge board? Like a light reflection?
Or is it changing direction due to pressure difference ?
I dont think it actually goes via barge board, when it turns it does so far before the barge board, like just behind the tyre it starts to bend prob from air coming from the side from under the nose. If you seen that cfd pic of the sauber you could imagine that air coming in there.
I think the relative vacuum behind the front wheel may help draw the vortex to viewer's left. Either that or there is a boundary layer of air in front of the barge board that deflects the vortex prior to its incidence.

Owen.C93
Owen.C93
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Re: Red Bull RB9 Renault

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It bends out way before reaching the bargeboard. That's why the turning vanes are for.
Motorsport Graduate in search of team experience ;)

Crucial_Xtreme
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Re: Red Bull RB9 Renault

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tony77g wrote:Red Bull had lost a skin of carbon diffuser on the end of the race
http://www.zaslike.com/
I don't believe RB "lost carbon fibre". You can see in images of free practice & Quali that the team just used different material in this area and between the two footplate strakes.

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raymondu999
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Re: Red Bull RB9 Renault

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ringo
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Re: Red Bull RB9 Renault

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meves wrote:@Ringo I might have missed something here but you're saying that instead of using ellipses they use circles (I'm assuming from your use of the word radii) or are you talking about a specific radius or a specific ratio of radius or another other measurements on the car? Or are you simply saying that the car has smooth surfaces and and a smooth as possible transition from one plane to another or that the transition from the sidepod to the floor is very smooth and gentle? I think I must be missing something from your description which just says use circles not ellipses.
I am referring to using a specific equation for the curvatures on the body of the car. The equation is that of a circle. So radii (arcs if you want to be anal, i just said radii because the arc shape is determined by it's radius) are used to form the sidepods. It's not just one arc from the side view as some think. The curvature is controlled on every square inch of the car.
The mistake most people make with design is that they use what looks good to the eye, or what they think is aerodynamic instead of what is fundamentally known,a curve of known equation that can be controlled. A simple curve such as that of an arc, gives better correlation with the wind tunnel and cfd, as it gives back more understanding. Wing theorist will figure out why the arc is an important equation.
The example that i have posted with the image of the car i built back in 2011, it was all done with rcs and only arcs (a few ellipses too) :mrgreen:
It was in plain view, but it wasn't obvious because people don't stop to think that a circle ranges from a point (zero raidius) to a line (infinite radius) as long as it obeys the equation of a circle. Now this is littered all over the 2009 car up to the current car. It was copied by the lotus team with the e20 and e21.
You see i don't mind what others think about the theory, as all they can and will do is talk. I usually have cfd and evidence to back up any theory i post on F1 technical. The car was built after i ran a test with 2 common types of sidepod designs against the arc shaped sidepod. At the time it was out of curiousity of the redbull's peculiar sidepod shape.
Test results have revealed many things, most importantly that the downforce advantage they enjoy is in excess of 10%.

I'd love for this to be taken as hogwash by the way, as it won't be popularly adopted as the new reason for everything itself such as the"coke bottle""flexy wings" and "rake" on an F1 car.
For Sure!!

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dren
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Re: Red Bull RB9 Renault

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So why wasn't the Lotus car spanking the competition too?
Honda!

cdsavage
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Re: Red Bull RB9 Renault

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Maybe some more specific examples of areas on the car with some images would help us understand your theory a little better.

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ringo
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Re: Red Bull RB9 Renault

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dren wrote:So why wasn't the Lotus car spanking the competition too?
'They were spanking the competition. The car was the second best car over the whole season.
If you notice their tyre wear, it was a good indication that the car wasn't running to 100% of it's potential.
Also take into consideration the consistency of the car in the stints and also the manner in which they went about a race with their strategy. That car was at half mast just like the redbull when it came to setup for qualifying and race.

Romain Grosjean proved that all it took was suspension geometry change to unlock the car, and it became sure podium grabber. Beating webber to the podium most of the time, in the steady manner that it drove also shows the strength of the desing.
I witnessed Lotus spaking everybody this season when it came to consistently fast pace. Take redbull out of the equation and you have the season's best car. The weakness was more to do with the team strategy and the drivers.

But back to the subject, just so that people understand what i'm getting at fully. The arc is used completely along the length of the car. It's not 4 or 5 arcs forming a line on the side pod. It's one consistent curve terminating to the floor or gearbox area. This has only been used in the redbull cars. How I know this? because we all have eyes to see. It doesn't exist in any car, no matter how far you want to look back in history. Find a car and I'll show the design philosophy is not there.
This is not common knowledge. I don't thing F1 engineers are god's or geniuses. I was hit with the same "f1 eng are smart, the tried it already" when I suggested that pullrod suspension is a no brainer. We need to move beyond that kind of thinking. Only gods have thought of every possibility.
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a rb car would have sufficed but this gives more clarity for the lines. Notice a constant curvature defining the shape.
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I also learned that there is a strong relationship with the top and sides, and if there is poor transition between both then the pressure zones are quite messy and downforce creation is poor. This is why the sauber sidepods have failed to realize it's intention. The goal is to have the taper of the top very much mirrored by the taper of the sides. This way you don't have much speed differentials with the top and bottom, hence "ugly" pressure distribution.

As said earlier big things make bigger impacts aerodynamically. A little vortex generator doesn't do much. It only improves areas of bad flow, like behind the wheels. or behind a wing. It mainly puts energy in low energy areas.

The sidepod and engine cover was the elephant in the room, no one cared to look into. The body of the car has the greatest surface area, even more than the wings. And we all know the basic aero equation has downforce directly proportional to area. Improving a major area gives greater improvement in downforce. Returning a 10% improvement in the body alone is a very healthy dose of downforce.
The arc also plays into why redbull can rake the car and still have so much stability. Rotating a circle doesn't change it's aerodynamic behaviour. If you have a piece of a circle as your sidepod, rotating it doesn't change it's behaviour as well.
So stability is another hallmark. They can turn the rake up all the way till the nose rubs the ground, and get secondary benefits from the front wing and diffuser. So you see how this is all tied in.
For Sure!!

eyalynf1
eyalynf1
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Re: Red Bull RB9 Renault

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@ringo - so have you run cfd on the model above? I would be curious as to the lift coefficient on the body relative to other designs.

timbo
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Re: Red Bull RB9 Renault

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ringo wrote:So stability is another hallmark. They can turn the rake up all the way till the nose rubs the ground, and get secondary benefits from the front wing and diffuser. So you see how this is all tied in.
So they have arcs on the mandatory flat bottom? :wtf: