Page 22 of 43
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 18:12
by wesley123
slits there would definetely not cause sepeartion in that are.
I am extremely confident in that it is flow seperation due to the pillar.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 18:34
by Matt Somers
PhillipM wrote:That's a massive section of flow seperation from that pylon if it is, I'm not buying that, I still think the vertical slits in the pylon are blowing there to cause the seperation.
What slits? I have the Hi Res image if you zoom into the area that's highlighted there are no slits....
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 18:51
by bhall
These slits.
And why would a duct this narrow cause so much flow separation?
Does the Coanda effect not apply to extremely narrow devices?
EDIT: And with regard to F1.com's odious explanation, the end plate fences have been on the car all year, and there's little reason to blow the area of the wing which sees the absolute least amount of pressure on the entire wing.
As I've said before, this is innovation when the rulebook is 77 pages long and loopholes get closed faster than Pastor Maldonado's temper.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 20:03
by PhillipM
Matt Somers wrote:
What slits? I have the Hi Res image if you zoom into the area that's highlighted there are no slits....
Those big vertical slits blowing at the initiation points of that seperated flow. As above....
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:05
by Huntresa
Such a narrow pillar wouldnt cause that much seperation or dusturbance,, if it would have been abit wider i could have bought it but no.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:07
by N12ck
Hi all, I have looked at the slits, and after looking at it all, and that they mentioned it will be used in Monza, I have realised that my original explanation was incorrect.
So how I think it works:
Drs closed: due to when the air gets to a certain speed it creates a blockage effect in the larger hole (above the beam wing and is directed to the rear wing at certain speeds) and stalls it out of the slots on the periscope image below.
when the drs opens, it takes air from by the endplates and blows out of the rear duct by the beam wing, creating a larger blockage effect directing air up the periscope and blowing out of the slits shown here.

Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:20
by bhall
There are no DRS inlets like the ones seen on the W03. This system is purely passive.
Air is collected by the airbox scoops and directed to the engine cover vent/wing duct assembly. At a certain pressure threshold, the air flow through the duct is sufficient to cause separation. It's a simple little thing to gain a little bit of time.
If the regulations still allow it, you'll see full-on Daffy Duct implementations up and down the grid next year when they can be incorporated into designs from the very beginning. Until then, they'll look like this.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:25
by N12ck
bhallg2k wrote:There are no DRS inlets like the ones seen on the W03. This system is purely passive.
Air is collected by the airbox scoops and directed to the engine cover vent/wing duct assembly. At a certain pressure threshold, the air flow through the duct is sufficient to cause separation. It's a simple little thing to gain a little bit of time.
If the regulations still allow it, you'll see full-on Daffy Duct implementations up and down the grid next year when they can be incorporated into designs from the very beginning. Until then, they'll look like this.
Lotus have already stated it uses the same loophole in the regulations as mercedes DRS system, and they said it works
with the drs system,
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:32
by bhall
Think about the changing pressure gradients across and under the wing when the DRS flap is open versus when it's closed. That's how DRS influences this system; it's not direct like it is with Mercedes.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:34
by Neno
N12ck wrote:bhallg2k wrote:There are no DRS inlets like the ones seen on the W03. This system is purely passive.
Air is collected by the airbox scoops and directed to the engine cover vent/wing duct assembly. At a certain pressure threshold, the air flow through the duct is sufficient to cause separation. It's a simple little thing to gain a little bit of time.
If the regulations still allow it, you'll see full-on Daffy Duct implementations up and down the grid next year when they can be incorporated into designs from the very beginning. Until then, they'll look like this.
Lotus have already stated it uses the same loophole in the regulations as mercedes DRS system, and they said
it works with the drs system,
yes it works, but it dose not depend on the drs system, their system working even when drs system is disabled. mercedes drs system working only with drs turn on,there for create double effect. lotus system working when drs is turn off (creating downforce), and when is turn on (creating same double effect like on mercedes). I can't explain better than this.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:37
by superdread
It can't simply be the wake, because that would split the flow, not detach it (although it would certainly help) but the flowvis-lines next to the triangular area are straight, so the flow really is detached from the wing.
Also it would be quite peculiar that a pylon in the middle of the wing stalls about one third of it. The already narrow rear wings are already so inefficient with the needed levels if downforce, reducing their effective width by one third would be mad, and all (at least most) the early DRS had a middle pylon with no blowing whatsoever.
Either air has become über-kinetic and produces enormous wakes behind pylons, making every team that has used a middle pylon on the (post-2009) narrow wings quite mad. Or Lotus blows their rear wing from the side (artificially enlarging said wake and detaching the flow, but only when the DRS is open).
There is no practical way to create a purely passive DRS (activated by environment, like total or dynamic air pressure), as DRS activation speeds differ greatly throughout the race, and as long as there is the option for having a human-activated one (if direct or indirect) the teams would not go for it.
PS The activation tubes for engaging the pressure switch, would go through the endplates and the beam wing. The pylon is so direct because you need a lot of flow energy to stall a wing from the side.
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 21:59
by N12ck
I will post this again, as I dont think the posters which posted after Bhallg2k seen it

(explanation on page before)
Re: Lotus E20 Renault
Posted: 30 Jul 2012, 22:39
by Huntresa
N12ck wrote:bhallg2k wrote:There are no DRS inlets like the ones seen on the W03. This system is purely passive.
Air is collected by the airbox scoops and directed to the engine cover vent/wing duct assembly. At a certain pressure threshold, the air flow through the duct is sufficient to cause separation. It's a simple little thing to gain a little bit of time.
If the regulations still allow it, you'll see full-on Daffy Duct implementations up and down the grid next year when they can be incorporated into designs from the very beginning. Until then, they'll look like this.
Lotus have already stated it uses the same loophole in the regulations as mercedes DRS system, and they said it works
with the drs system,
Well yeah it uses the same loophole, but that loophole is just to use the DRS for a 2nd action, and werent you the one that said there were no holes ?

Re: Lotus E20 Renault
Posted: 30 Jul 2012, 22:44
by N12ck
Huntresa wrote:N12ck wrote:bhallg2k wrote:There are no DRS inlets like the ones seen on the W03. This system is purely passive.
Air is collected by the airbox scoops and directed to the engine cover vent/wing duct assembly. At a certain pressure threshold, the air flow through the duct is sufficient to cause separation. It's a simple little thing to gain a little bit of time.
If the regulations still allow it, you'll see full-on Daffy Duct implementations up and down the grid next year when they can be incorporated into designs from the very beginning. Until then, they'll look like this.
Lotus have already stated it uses the same loophole in the regulations as mercedes DRS system, and they said it works
with the drs system,
Well yeah it uses the same loophole, but that loophole is just to use the DRS for a 2nd action, and werent you the one that said there were no holes ?

yes I couldnt find any initially, however I have now found one, so I have revised my theory, at least I am trying to come up with some workable explanation, the holes which people had 'found' before were not holes, we now know this is a hole, so I have now offered a theory above, I believe my theory is workable,

Re: Lotus E20 Renault
Posted: 30 Jul 2012, 22:45
by Huntresa
Eh maube you should link that "hole" then so we all can see ??