Sucked wing idea

[manchild]

I was thinking... ram-air effect that feeds the blown wing is immeasurably lesser that what inverted functioning would be. Ram-air generated pressure/volume/speed depends on inlet diameter and the speed of car, while sub-pressure of sucked tube depends on capacity of suction device - in this case the engine.

It would even rise as speed decreases and so do revs, right?

So, what I'm recommending would be instead of blowing wing trough aperture at the back, there should be aperture on wing's top connected to airbox. Siphon shape would prevent the air stream from entering duct, and simultaneously direct sucked air in direction of main air stream.

Since engine revs are much more constant than speed of the car, this would be more effective on any part of the circuit.

*This is just a quick sketch, had no time to think how Mclaren's airbox looks like.

[wesley123]

so actually this duct activates on low speeds actually preventing the stall of the rear wing? That would actually be an genius idea, would actualy increase the downforce as there will be an lower pressure behind the wing enhancing its function(assuming it works similair as an diffuser)

Then when the speeds become higher it will stop sucking air allowing stalling(wich ai assume if first one was correct)

Actually, that idea is simply genius, it is the same idea of an F-Duct, works similair the only difference it is that it actually sucks air.

Creating that sucking effect could actually be easy as you only have to allow an vacuum at the slit. The only 'bad' thing of it would actually be the way it flows to the airbox, wouldnt it actually stop this sucking at a point because of the pressure in the bend in it? IMO i wouldnt let the pipe flow to the airbox, instead just let it blow out by itself in a same way as is done with the F-Duct, then there it can create extra downforce by blowing air where it is needed.

[manchild]

Thanks for the compliments, but I think you got me partially wrong. Blown wing has aperture/slit at its bottom - lower plane, while I'm suggesting aperture/slit at top - upper plane of the wing.

So, no stalling but almost constant additional downforce which would enable team to run wing on lower angle and therefore reduce drag while maintaining same downforce at more constant level.

[Skunk0001]

The suction of the engine is dependent on revs, not car speed, since the car has gears. So wouldnt this effect the downforce in every gear before the upshift?

I could imagine that would get 'interesting'.

Either that or I missed something.

Maybe they could create a similar effect, but only based on speed, with some nicely shaped wheel rims/brake ducts and tubing, since the wheel speed is directly dependent on car speed.

[wesley123]

so if i understood correctly this device sucks the air away at the top of the wing?

[manchild]

The suction of the engine is dependent on revs, not car speed, since the car has gears. So wouldnt this effect the downforce in every gear before the upshift?

Indeed, but as I've said, revs are much more constant than air speed. So, if that created no upturns for blown wing this should be care-free. Car speed varies from 80kph to over 300kph, while revs don't drop that much from their peek.

so if i understood correctly this device sucks the air away at the top of the wing?

Yes.

[wesley123]

that woould actually work great, it wont even add that much drag, maybe even decrease this. It is much more easier for the air to travel between the end plates due to the lower pressure, this increases downforce too

[marcush.]

why rear wing?

this is the solution to build a system to retain front downforce when running in slipstream conditions .couple the sucking tube to the adjustable wingflap ...(increasing wing AoA will open the port!)and voila mega front downforce in the corner leading to the straight so you CAN keep under the gearbox? Move out of the slip stream retract the flap and use the speed ...

[manchild]

why rear wing?

this is the solution to build a system to retain front downforce when running in slipstream conditions .couple the sucking tube to the adjustable wingflap ...(increasing wing AoA will open the port!)and voila mega front downforce in the corner leading to the straight so you CAN keep under the gearbox? Move out of the slip stream retract the flap and use the speed ...

Rear only, front only, both I'm all for it.

[autogyro]

I think it could only work at high engine rpm/air volume.
This would only be effective in a hybrid system that allows the engine to run close to constant rpm when needed.
I am not allowed to say any more, or I will be accused of promoting my ideas.
Srange that.

[marcush.]

why rear wing?

this is the solution to build a system to retain front downforce when running in slipstream conditions .couple the sucking tube to the adjustable wingflap ...(increasing wing AoA will open the port!)and voila mega front downforce in the corner leading to the straight so you CAN keep under the gearbox? Move out of the slip stream retract the flap and use the speed ...

Rear only, front only, both I'm all for it.

+1

=D> =D> =D> cool idea.

[Carlos]

Manchild - This reminds me of several 2007 aero threads and some of my references to different ideas - that were (sigh) widely ridiculed as extreme in the past - but are suddenly fashionable:

Circulation control wing:
http://en.wikipedia.org/wiki/Circulation_control_wing
http://www.airspacemag.com/history-of-f ... c=y&page=1
http://pdf.aiaa.org/preview/CDReadyMFLC ... 6_3011.pdf

Blown flap:
http://en.wikipedia.org/wiki/Blown_flap

Leading edge flap:
http://www.zenithair.com/stolch801/design-wing.html
http://adg.stanford.edu/aa241/highlift/ ... intro.html
http://www.pprune.org/forums/showthread.php?t=239334
http://en.wikipedia.org/wiki/Leading_edge_slot

[piast9]

I don't understand the idea. Why would you like to lower the downforce/reduce drag at full throttle - high revs situations? How would it work for example at the exit of fast corner?

[manchild]

I don't understand the idea. Why would you like to lower the downforce/reduce drag at full throttle - high revs situations? How would it work for example at the exit of fast corner?

Let me rephrase it - The pressure on top of the wing is higher than pressure within the airbox. Wing is hit by air at full span with speed and volume identical to one that hits airbox inlet, but airbox faces only the air that enters trough inlet, and inlet can pass less air than the engine can consume. Therefore, engine still does suck the air in because ram-air effect can't feed it enough.

http://www.f1technical.net/articles/4

It is commonly thought that the purpose of this is to 'ram' air into the engine like a supercharger, but the airbox does the opposite. The carbon fibre duct (1) gradually widens out as it approaches the engine, effectively creating a venturi and a suction effect on the small air inlet.

Now, since the engine does act as air pump, it would increase the amount of air that hits wing's upper plane thus increasing downforce.

Or if you don't agree - calculate the volume of air traveling at 350kph that passes trough approx. 150mm diameter inlet, and than compare that with volume of air that is consumed by 2400ccm engine that revs at 18000 rpm.

Even the FIA regulations impose that engine block ventilation pipe must be drained to airbox.

[wesley123]

@Carlos; aren't the first 2 things in some way actually similair to the F-Duct? Tey both make use of blown air from somewhere else, only their use is different, in airplanes it is used to feed the wing in stall situations, in F1 it is used(in the F-Duct way) to stall the wing, same ideas, different use.