Footplate strakes

[shelly]

Just a little comparision

I use this interesting picture posted by emmepi27 as a starting point for discussing a detail that has a significant impact on rear downforce: the footplate strake.
It predates ebd and coanda, and will live on in 2014 with further improvements to gain back some of the notorius "sealing effect".
First thing that comes to my mind when seeing this comparison is that the redbull solution seems more deatiled and refined; thay were also the only team that managed to get the double strake solution working (mclaren tried with no success)

[hollus]

Those strakes in the Red Bull also have fillets. They have properly, purposely shaped fillets. In comparison the Lotus has no fillets and the others have "rounded edges", but only in the Red Bull it looks like somebody calculated that they should have that particular shape and no other.
Actually, about everything in the RB9 seems to have purposely shaped fillets, while about every other car seems to have plenty of entrant 90 degree angles for no obvious reason.

[shelly]

yes I find it starange. It is not that the other teams do not know about fillets or are not able to manufacture them - so why the difference?

[strad]

In comparison the Lotus has no fillets

What I notice is they all have legal non holes in the floor, EXCEPT Lotus.

[horse]

Discussing the fillets, to me it makes sense to try and use the tire motion to produce vortices to go inboard of the tire and under the floor. I think the "multi-element" part of this helps to increase the intensity of the closest section to the tyre.

I've wondered if it might be possible to orientate them along the long-axis of the car, with increasing size and the largest section being the closest to the centre line. I know that seems a bit counter-intuitive, but the velocity vectors near the tyre are going to exhibit some sort of downward + perpendicular motion, so it should work.

[Just_a_fan]

thay were also the only team that managed to get the double strake solution working (mclaren tried with no success)

I wonder if that is because of the RedBull tunnels. They obviously are very powerful conditioners of the flow along the sidepods (helping to create front downforce too no doubt) that the flow to the double strakes (along with the exhaust from the ramp) is probably much more defined.

I know that all of the cars are designed as a whole system, but the RB just feels like that process has been taken to the next level.

[shelly]

Browsing the internet for vortice found an artickle on turbomachinery (http://turbomachinery.asmedigitalcollec ... id=1467090)

with a very interesting picture

Interesting to compare with the rear wheel zone if you substitute the turbo blade with the winglet closest to the rear wheel

[shelly]

Edit: Its not a cutout, its just some material they put in that area cause if it was cutout we would see black asphalt which we dont and you can see the exhaust gases have burnt a bit at the beginning of it.

from the protective material placement we can think that on the redbull the exhaust flow partly between the two strakes and partly (mostly?) inboard of the inner strake

[shelly]

Guys by vortex you mean something like this?



Makes me wonder why they removed it in Australia after running it throughout winter testing. Maybe they realized they really need it now after all??? Hmm. Anyway can't wait to see the car on track with its full package for this weekend.

[shelly]

besides the single- double strake, there is big difference inthe shape of the last bit in front of the wheel: rb8 with the wider one, no flick up on the inner side, biggest slot between element and rest of floor, best (together with ferrari) sealing between wheel and element.

Maybe redbull have been able also to tune this element into a drag reduction air dam, like the ones usually seen on most production cars. That could explain part of their recent high speed performance

[SectorOne]

What I notice is they all have legal non holes in the floor, EXCEPT Lotus.

Lotus like the others have legal holes. If you look closely you can see the cutouts at the end of each hole.