Lotus E20 VD

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rscsr
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Joined: 19 Feb 2012, 13:02
Location: Austria

Re: Lotus E20 Renault

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Cuky wrote:
Kiril Varbanov wrote:Image
Why do you thing they are blowing down in to the diffuser??

This is their way of making a passive F-Duct. While they can't get airstream to the wing through shark fin, as they are forbidden to contact with rear wings, they have routed it through central pylon. When duct is not activated air goes from intakes straight to the exit in the middle of the car, just under the beam wing (that large tunnel marked here in blue). When car is at certain speed F-Duct is activated and air goes from intakes, through central pylon and on to the wing. I am not sore where they are venting it, though I don't think it will be too long until someone spots that place
I would actually think, that the way it works would be the other way round. At first we need to assume, that the hole in the main plane is on the top in the shadow of the flap and below the T of the Lotus sponsoring.
Then when the DRS is closed, there is a relatively low pressure at the and of the hole and through the duct comes high pressure --> the air flows through the main plane.
When the DRS is open, then there is a relatively high pressure on the end of the main plane --> not much air is flowing through the ducting and the wing may stall.

PhillipM
PhillipM
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Re: Lotus E20 Renault

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^^Okay, looks like maybe there are vertical slits in the central pillar itself?

MarkedOne8
MarkedOne8
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Joined: 08 Feb 2012, 10:30

Re: Lotus E20 Renault

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Air is not going from RW down to diffuser.It about opposite direction.It goes from rool hoop intakes up to DRS mechanism.When DRS is not active, DRS mechanism closes the central RW tube, so the air from rool hoop goes to beam wing or beam wing + diffuser.DRS active, DRS lower mechanism opens tube hole and makes stalling effect for rear wing.Maybe?
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nacho
nacho
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Joined: 04 Sep 2009, 08:38

Re: Lotus E20 Renault

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No holes in the wings, so the central tube has slits right at the contact point, so it has air going at two directions. What I don't understand is why they need to blow the monkey seat to make it work. Maybe they use it just as an additional bonus?

i70q7m7ghw
i70q7m7ghw
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Joined: 12 Mar 2006, 00:27
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Re: Lotus E20 Renault

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MarkedOne8 wrote:Air is not going from RW down to diffuser.It about opposite direction.It goes from rool hoop intakes up to DRS mechanism.When DRS is not active, DRS mechanism closes the central RW tube, so the air from rool hoop goes to beam wing or beam wing + diffuser.DRS active, DRS lower mechanism opens tube hole and makes stalling effect for rear wing.Maybe?
Agree with this. For me it's clear with DRS closed air goes from the roll hoop to the beam wing. When DRS is open it would appear the airflow then goes to the rear wing main plane. It's quite how it does this that we probably need to understand.

mike
mike
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Joined: 10 Jan 2006, 13:55
Location: Australia, Melbourne

Re: Lotus E20 Renault

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if there was no hole then why is there no flow vis on the slit for the new wing but it is covered in flow vis in the old wing??
if the triangle was created by middle pillar then why is there no triangle for the macca rear wing?

Huntresa
Huntresa
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Joined: 03 Dec 2011, 11:33

Re: Lotus E20 Renault

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I thought you were allowed slits in the main plane but just not as big as 2010 ? So the effect was gr8tly reduced.


Edit: To stall either the top rear wing or the beam (lower) rear wing, you need to blow a slot. In the post 2010 rules, slots are banned in any section of the rear wing (via a 100mm minimum radius rule); this ban applies to all three wing elements aside from the middle 15cm. So to use the DRS duct to blow a rear wing slot, all you’ll stall is the very centre section of wing. This area creates very little induced drag (most of that’s created at the wing tips), so stalling it will not improve top speed by much. Thus it will provide very little benefit.


It does look in that pic like it is the middle 15cm, no ?

PhillipM
PhillipM
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Joined: 16 May 2011, 15:18
Location: Over the road from Boothy...

Re: Lotus E20 Renault

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Depends whether they can get that seperation to spread once started I suppose? Would point towards possible reattachment issues at some point though.

bhall
bhall
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Joined: 28 Feb 2006, 21:26

Re: Lotus E20 Renault

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PhillipM wrote:^^Okay, looks like maybe there are vertical slits in the central pillar itself?
I noticed those quickly, but I didn't think much of them. However, I'm now pretty sure they are in fact the vents for the system.

I think they do indeed just help to stall the center portion of the wing (rectangular highlight), and I think the beam wing enclosure around the engine cover vent (circular highlight) is essentially just a diffuser to help draw out air from the vent.
Image
(Click to enlarge)

To bolster the idea that the duct slits are the vents, you can see below that they were covered so the team could differentiate the effects of the slits from the effects of the duct itself.
Image
(Click to enlarge)

I hope this is my final answer, because I hope my OCD on this subject has run its course.

PhillipM
PhillipM
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Joined: 16 May 2011, 15:18
Location: Over the road from Boothy...

Re: Lotus E20 Renault

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Part of the monkey seat solution might be to generate enough low pressure at the duct outlet to stop the system switching on when in the low speed corners?

bhall
bhall
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Joined: 28 Feb 2006, 21:26

Re: Lotus E20 Renault

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Perhaps. But, I'm more inclined to believe it just helps to extract air from the vent because the vent had to made considerably smaller to accommodate the new duct.

mike
mike
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Joined: 10 Jan 2006, 13:55
Location: Australia, Melbourne

Re: Lotus E20 Renault

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Image
its the same as the macca system in the monkey seat area, the commentary says the system is automatic and has nothing to do with DRS.......

Ozan
Ozan
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Joined: 05 Jan 2012, 01:50

Re: Lotus E20 Renault

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Image

Blue circle is the reflection of the red one..

(right click-view image for bigger res)

aral
aral
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Joined: 03 Apr 2010, 22:49

Re: Lotus E20 Renault

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Ozan wrote:
Blue circle is the reflection of the red one..

(right click-view image for bigger res)
No, blue circle is a reflection of the curved side support immediately above!

MarkedOne8
MarkedOne8
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Joined: 08 Feb 2012, 10:30

Re: Lotus E20 Renault

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Am I the only one who noticed the pace of Kimi in Q1 on MEDIUM tyres?
Even Grosjean succeeded to qualify himself in through Q3 on MEDIUM tyres.Only Rosberg an Hamilton were able to do the same, but not as fast as Kimi.
Lotus solved qualifying problems?Kimi faster for 0.992 seconds comparing to Grosjean?
Fernando Alonso is the best pay-to-drive driver in F1 with the biggest amount of money behind him.
http://f1bias.com/2012/04/05/truth-abou ... nder-2008/