Red Bull RB5

[modbaraban]

Come on mod, diffuser meeting with the wing makes it look great, can't you tell, which means the world for us picture-aerodynamicists!

As a seasoned picture-aerodynamicist I can't agree. It looks like an AD-board from side view.

[djos]

And that helps... how?

Besides why not have the best of both solutions by adding some additional channels on the sides:

Also RB5 has quite a clearance under the rear wing where most cars have wing supports and additional planes. Maybe the flow under the wing help diffuser so much that they need most of the diffuser air exit down the middle. I guess that may accelerate the flow. Oh, I almost forgot to add the exhaust exits to the equasion. Hmmm

Connecting the end-plates to the diffuser has i believe 2 main benefits:

1/ removes the need for the center upright supports everyone else has providing less drag and lowering the center of gravity.

2/ it allows RBR to virtually extend the effective length of the diffuser increasing its efficiency by what i imagine is a sizable margin.

Btw, they do have a small diffuser extension on either side of the rear wing end-plates.

[timbo]

I think the main benefit comes from coupling of the diffuser with the lower profile of the rear wing.

[axle]

And the narrower diffusor will lead to less drag, and that seems to have been a major effort looking at the tail of the RB5.

Less drag and as much DF as a wider diffuser = bl00dy good idea

I actually expect teams will go this way with a William/Toyota extension.

[kilcoo316]

What's the advantage of limiting the diffuser width? All the other cars' diffusers are wider than the rear wing.

I would expect that to change through the season - no reason why they cannot stick two further diffusive tunnels either side of the current fixture.


As for the advantage it provides - its reducting the pressure seepage around the diffuser sidewall that will result in a loss of downforce.

(As I'm sure most of you know - at a wingtip, a wing produces zero lift/downforce)

With the diffuser effectively being a very low aspect ratio and very highly loaded wing, even a small improvement in the lift distribution can have quite tangible gains.


As for why I think it will change eventually - stick two extensions on the sides and you get the endplate effect, the wingtip effect is still reduced for the central diffuser, and you get a bit more diffuser downforce.

But it'll probably be done in tandem with front wing adjustments to keep the aerodynamic balance right.

[PNSD]

I think it has alot to do with coupling of the lower element and the diffuser and generally the benifits of a deeper endplate (effectivley increasing aspect ratio). Id also go as far as saying better flow control at the rear and better sealing the flow above the diffuser. At least this is my interpretation of it. Check out the group C cars with their deep endplates.

[Ian P.]

The voice from the top....

http://www.racecar-engineering.com/news ... w-rb5.html

[scarbs]

The lower portion of the rear wind endplate can extend further behind the diffuser. This prevents the inwash coming in from behind the rear wheels, thus Newey has found another way to maintain the low pressure below the car, rather than using the full allowable width of the diffuser.

[animal ed]

I`m more curious about KERS. As i know they didn`t test it yet so i wonder is it really designed to carrie one? We all know (guess) benefits comparing to use it or not... or designed to carrie one but instead KERS mounted, using ballast all over! I assume that nonKERS designed car is superior comparing the KERS ready but non mounted but how much?
...and appologize about my english (not my fault - google) i`m bit rusty - speak well but have difficulties with writing...

regards

[axle]

I`m more curious about KERS. As i know they didn`t test it yet so i wonder is it really designed to carrie one? We all know (guess) benefits comparing to use it or not... or designed to carrie one but instead KERS mounted, using ballast all over! I assume that nonKERS designed car is superior comparing the KERS ready but non mounted but how much?
...and appologize about my english (not my fault - google) i`m bit rusty - speak well but have difficulties with writing...

regards

Your English isn't bad so don't worry

You post an interesting question too...have then ommitted KERS from the RB5. They certainly have not said as much.

[modbaraban]

I`m more curious about KERS. As i know they didn`t test it yet so i wonder is it really designed to carrie one? We all know (guess) benefits comparing to use it or not... or designed to carrie one but instead KERS mounted, using ballast all over!

Well according to Newey (link by Ian P.) the car is designed for KERS. The question is indeed interesting. I think in early stages of KERS development the benefits of having working KERS onboard rather than more ballast to play with are doubtful. But turning down the KERS technology altogether in current conditions is quite too risky in the long term.

I have a question after reading Newey's interview. What's with the flat vs. V-shaped bottom? Is it required by the 2009 regs or something they came up with for better efficiency?

PS: scarbs, thanks for clarifying it. In essence then they trade the width of the diffuser for its 'length'.

[Saribro]

I have a question after reading Newey's interview. What's with the flat vs. V-shaped bottom?

I think he means on the front part of the tub, the point where the lower suspension arms mount. (at least that part is now a shallow V, rather than flat)

[modbaraban]

I have a question after reading Newey's interview. What's with the flat vs. V-shaped bottom?

I think he means on the front part of the tub, the point where the lower suspension arms mount. (at least that part is now a shallow V, rather than flat)

Oh that... I noticed it too. It looks almost like a keel.

[animal ed]

Well according to Newey (link by Ian P.) the car is designed for KERS. The question is indeed interesting. I think in early stages of KERS development the benefits of having working KERS onboard rather than more ballast to play with are doubtful. But turning down the KERS technology altogether in current conditions is quite too risky in the long term.

My doubt about this is more because they have B team called red bull in italian language (guess what - even with italian powerplant) so they can take time and sacrifice them for testing and research program during the season ... maybe STR will be fully KERS ready and equpped, or opposite ... main question is will it be enough extra 60 kw lasting for 6,6 sec during the lap against better balanced car with bigger fueltank and better placed ballast?
My post is placed here because i`m almost certain that new STR will have not just pull-rod rear suspesion same as RBR.

[modbaraban]