Lotus E21 Renault

[shelly]

The red strake is used to create a vortex that rolls from the outside (high pressure in front of the wing) to the inside, and then flows in line with the diffuser edge, close to the tire, providing a seal from tyre squirt. The exhaust blowing exactly there accelerates and strenghtens that vortex.

The vortex created from the strake is close to the footplate vortex, and is rotating in the opposite sense, Ideally you would like to blow the exhaust between these two voritces, in order to achieve the famous "sealing" effect

[stefan_]

I knew that the "metallic vane" is there to stop the lateral flow coming and interfering with the exhaust flow and changing its direction.

[Blackout]

The red strake is used to create a vortex that rolls from the outside (high pressure in front of the wing) to the inside, and then flows in line with the diffuser edge, close to the tire, providing a seal from tyre squirt. The exhaust blowing exactly there accelerates and strenghtens that vortex.

The vortex created from the strake is close to the footplate vortex, and is rotating in the opposite sense, Ideally you would like to blow the exhaust between these two voritces, in order to achieve the famous "sealing" effect

Thanks

[Donuts]

Yes.

I'm still puzzled by some aspects of the design of the rear of the car. Especially by the way that metallic vane (red) is placed. Someone could explain how that vane works ? It's obviously important in managing the airflow near the tires, but it seems to obstruct the way to the top of the diffuser... Looks like a compromise...
That was the serious part of my post. Now the less serious one:
Personally i would remove the back wall of the 'cross tunnel' (green). The 'ramp' would then 'levitate' above the floor and never touch it, so more air (blue) can flow freely toward the diffuser. And I would move the tunnel (yellow) forward. : P

(Made some mistakes in coloring the yellow tunnel)
http://www.servimg.com/image_preview.ph ... u=14795526

Hmm, surely, looking at the pics on the previous page, the tunnel(yellow) is far wider than what you've marked? Maybe I've missunderstood you? It looks to envelop the whole coke bottle flow.

[Blackout]

Yes it is. It's a rough drawing.

[stefan_]

Barcelona (Test 3, Session 2) - Day 4 (03.03.2013)




via Craig Scarborough

[Blackout]

Edit
https://pbs.twimg.com/media/BEbn2quCcAA5SRk.jpg:large

[RicerDude]

Edit
https://pbs.twimg.com/media/BEbn2quCcAA5SRk.jpg:large

Is that legal?

[shelly]

@stefan: the vane/strake was there on the e20 also at the beginning of that season (see for example http://www.f1technical.net/forum/viewto ... &start=360), when thy did not have any coanda aided ebd. So its primary function is independent of exhausts, and it is to generate a small but effective vortex using an existing structure on the car, i.e. the high pressure buildup in front of the wheel.
The vortex is mad more powerful by the exhausts, that stretch it along its rotation axis

[stefan_]

Thanks for the explanation.

[Blackout]

Lotus are missing something all other top teams have, and that is a suspension arm integrated covered driveshaft. I'm wondering how much of an effect having the magnus effect still in place will be evident on this Lotus which certainly appears to be an otherwise great car, on paper so far anyway.

E21's lower rear wishbone and the transmission rod are on the same plane but they are not close to each other. And the track rod is lower. Can they move them (wishbone and/or trackrod) in order to cover them with the transmission rod?

Pic also shows that they tested different rear wheel winglet sizes/shapes

http://www.servimg.com/image_preview.ph ... u=14795526

Edit: it's the other way around; wishbone is lower. Driveshaft and trackrod have same height.

[Hail22]

Another angle of the enclosed E21 Exhaust housing:

[GrizzleBoy]

Could that piece of metal covering be defined as part of the actual exhaust?

Could they actually bring the exhaust out of the bodywork like that and have it rest on top of the metal plate to make a similar shape?

[beelsebob]

Could that piece of metal covering be defined as part of the actual exhaust?

No, if it was, it would be illegal, because it's the end, and it's not a right circular cylinder.

[henra]

The vortex created from the strake is close to the footplate vortex, and is rotating in the opposite sense, Ideally you would like to blow the exhaust between these two voritces, in order to achieve the famous "sealing" effect

what you call footplate vortex is the one on the lower side of the floorplate I assume, i.e. the one created by the lower side of the bargeboard.

The vortex of the strake will ilkely add to the vortex created by the upper side of the barge board moving through the undercut alongside the sidepod and above the floorplate. This vortex will be rotating on the upper side to the inside of the car, thus in the opposite direction of the lower 'floorplate vortex'.
It would be interesting to see a high resoution CFD of the Ramp solution. I'm wondering how much of the upper side vortex (from the barge board) through the undercut will go into the tunnel and what happens to the remaining vortex: will it move straight ahead along the strake to the diffuser edge ? That's what I assume is the goal. But does it work that way?