Reducing the drag of a two element wing through stall

[Mysticf1]

I couldnt agree more, pure fantasy, everyone is getting bored / edgy for the new season...only 5 days togo people.

[Confused_Andy]

Finally I'm glad someone's said it, it just seems like a crazy idea that something as small as that inlet could even contain the pressure to go as far as the end of the car 2/3 meters away... Even if it could hold the pressure to the wing surely all that comes out the back is just a dribble nothing substantial, I dont even understand how they could place a tube under the inlet seen as its where the suspension arms meet and theres a pannel for it on the other side...

If it turns out to be the truth however i'll eat my hat but until its proven it just seems such a stupid idea that people have become obsessed with.

[Giblet]

Then don't play if you don't want to try to figure it out.

Some of use enjoy it, and we discuss it. Telling us not to is basically just lame. I find it fun, and we might be on to something, and this kind of talk brings more technical minds to the forum.

Confused_Andy. A vaccuum cleaner hose can be really long, and if the hose has no holes in it, it's not like the pressure stops.

Shaddock, you are talking like the many that think the wing stalls completely at a set speed. The air out the back as far as I can figure, partially stalls the wing, making it less effective than it would be without the blown gap at the back. Making a steep wing at as a less steep wing at speed.

The snorkel IMO is just a control, a hole in a pipe like a flute. Covering a hole changes the 'pitch', or the 'pressure'.

As well, just because we get a friday practice in 5 days, doesn't meant that Mclaren have to give us full disclosure of how it works. We may be speculating until far into the season, so if you don't want to play, go away.

I like playing in this sandbox, and won't be told not to.

[Mysticf1]

No one is stopping you Giblet, or suggesting that either, we are simply stating our opinion...criticism is all part of this sandbox too.

[autogyro]

No one is stopping you Giblet, or suggesting that either, we are simply stating our opinion...criticism is all part of this sandbox too.

Criticizm is fine but there is a slot in the rear wing and there is a join with the shark fin.
So now all those who wish to criticize, perhaps you can all explain exactly what is NOT happening.
You have no argument up to now whatsoever.
Sign of the times and the weedy generations today, take the easy way out.
You all have the right to criticize but some are starting to take the p---.
Give up before you begin, I have no problem with beating you on that score.
I am an expert at it.

[Ganxxta]

+1, this thing is to small to produce an airstream to the rearwing, the airbox channel idea is more likely used...

Read the last few pages. It doesn't channel air for the wing, just air to a fluidics switch, which contains NO moving parts and does not require much flow at all.

I did, at least the last ~15 pages... But I still can't understand why you have to have a snorkel in front of the Driver just for the fluidic switch (besides the knee story ), I mean wouldn't it be easier to use the same channel in the airbox or whereever for the switch (maybe with a seperation in it only for the switch)?

[Mysticf1]

I agree theres a slot, its joined by the shark fin which provides air to that slot, i dont agree that a driver controls that with his knee. Just look at the space involved around the drivers legs and the lateral G forces experienced. In my opinion is most likely a cooling vent. Sometimes the simplest answer is the right one no?

[nacho]

About the snorkel: was it ever discovered why the F2007 had a scoop on the front?

http://trendsupdates.com/wp-content/upl ... macher.jpg

[FGD]

I'm guessing the snorkel ahead of the cockpit is for cooling... perhaps simply for driver comfort.

The real topic is how McLaren have designed their rear wing to stall.

Here's my theory:

McLaren are funneling some hot air from the engine bay through the sharkfin into a hollow rear wing.

The only known oulet for the high pressure, hot air in the hollow rear wing is a thin slit running the width of the rear wing.

I'm guessing that as pressure builds within the wing, the wing expands slightly. The thin slit also expands, allowing more hot air to pour into the vacuum behind the rear wing.

The wing won't stall but downforce generated by the wing will fall off. Just a simple idea really.

[autogyro]

Dear SLC,

I find it a bit curious that you mention that the induced drag component is negligible for an F1 wing, yet then try and explain that the usual aerodynamic rules of thumb do not apply for an F1 wing because the rear wing is tilted at such an angle that stalling it will reduce both lift and drag.

I believe it is precisely the induced drag that is reduced by stalling the wing, and that it is the phenomenon of induced velocity that requires the geometric tilt of the rear wing needs to be so large in the first place. The reason that the rear wing is tilted at such a steep angle is that, by producing lift, it induces an upward velocity component onto itself, so the actual angle of attack of the wing in the airflow is smaller than the geometric one. Compared to a 2D (large span) situation, the induced velocity rotates the "lift" vector backwards. Therefore, when reducing "lift" (stalling) this causes a decrease in drag, just as your picture correctly shows. On a wing of a much larger span, the stalling of the rear wing components would however most likely not bring any drag benefits.

The further the air has to go the lower the pressure, this is why the upper element of wings are near vertical. It works with the bottom wing, which helps to keep the flow attached to the upper wing element by directing the flow upwards.
A slot on the rear of the upper element helps to keep the boundary layer attached and allows an even steeper wing with even lower pressures.
As the wing becomes steeper the centre of low pressure angles further rearward but the decrease in pressure is bigger than the effects from the change in angle, so the DF Resultant, (which has to be vertical to the cars travel) is higher.
Take away this low pressure by blocking off the slot flow and DF goes right down with a reduction in the drag from the low pressure area behind the wing. It only needs a flow of air introduced at an angle to the mainflow in the shark fin, to negate the outlet air at the slot and create this change.

[nacho]

Maybe it is designed to be rigid enough to pass the FIA tests and just flexible enough to let the air flow squeeze out at high speeds. Or does the FIA test only test flexibility at certain direction, so at extreme high speeds the rear wing could flex at a certain way, just enough to open the slot for air to flow out?

[autogyro]

The snorkel is at least in a position where the air flow is smooth and unaffected by anything else. Ideal if used for varying the volume of a control flow.

[rifrafs2kees]

Then don't play if you don't want to try to figure it out.

Some of use enjoy it, and we discuss it. Telling us not to is basically just lame. I find it fun, and we might be on to something, and this kind of talk brings more technical minds to the forum.

Confused_Andy. A vaccuum cleaner hose can be really long, and if the hose has no holes in it, it's not like the pressure stops.

Shaddock, you are talking like the many that think the wing stalls completely at a set speed. The air out the back as far as I can figure, partially stalls the wing, making it less effective than it would be without the blown gap at the back. Making a steep wing at as a less steep wing at speed.

The snorkel IMO is just a control, a hole in a pipe like a flute. Covering a hole changes the 'pitch', or the 'pressure'.

As well, just because we get a friday practice in 5 days, doesn't meant that Mclaren have to give us full disclosure of how it works. We may be speculating until far into the season, so if you don't want to play, go away.

I like playing in this sandbox, and won't be told not to.

I have no issues with discussion. But this "conjecture"(dare I say again) has been exhausted. Second issue is there're always a loss of vacuum or pressure efficiency the longer the path of action even without leaks. Why would mclaren with all that real estate of a car they have, put that thing on the nose, which by the way isn't electric; to control something on the tail end of the car? We've been fed enough of this stuff. The quality of the posts believe me or not, haven't been that good of late. It's been snorkel, snorkel, snorkel, snooorrrrkeeeeel............with no end in sight.

[volarchico]

About the snorkel: was it ever discovered why the F2007 had a scoop on the front?

http://trendsupdates.com/wp-content/upl ... macher.jpg

That looks surprisingly like the McLaren snorkel, but the F2007 has no sharkfin to control...hmm?

[Giblet]

Then don't play if you don't want to try to figure it out.

Some of use enjoy it, and we discuss it. Telling us not to is basically just lame. I find it fun, and we might be on to something, and this kind of talk brings more technical minds to the forum.

Confused_Andy. A vaccuum cleaner hose can be really long, and if the hose has no holes in it, it's not like the pressure stops.

Shaddock, you are talking like the many that think the wing stalls completely at a set speed. The air out the back as far as I can figure, partially stalls the wing, making it less effective than it would be without the blown gap at the back. Making a steep wing at as a less steep wing at speed.

The snorkel IMO is just a control, a hole in a pipe like a flute. Covering a hole changes the 'pitch', or the 'pressure'.

As well, just because we get a friday practice in 5 days, doesn't meant that Mclaren have to give us full disclosure of how it works. We may be speculating until far into the season, so if you don't want to play, go away.

I like playing in this sandbox, and won't be told not to.

I have no issues with discussion. But this "conjecture"(dare I say again) has been exhausted. Second issue is there're always a loss of vacuum or pressure efficiency the longer the path of action even without leaks. Why would mclaren with all that real estate of a car they have, put that thing on the nose, which by the way isn't electric; to control something on the tail end of the car? We've been fed enough of this stuff. The quality of the posts believe me or not, haven't been that good of late. It's been snorkel, snorkel, snorkel, snooorrrrkeeeeel............with no end in sight.

The Ferrari duct is in a completely different place. Not right where a drivers left knee is.

A switch is not allowed. It can not be part of the car. there is nothing in the rules that says a drivers knee can't plug a hole. That is why the 'ridiculous' idea of a knee is even plausible, to skirt the rules.

After reading about teh fluidic switch, that only needs a tiny change in pressure to get air from another source, like maybe the diffusers second deck?

Everything i this thread once the fluidic switch was found, is completely plausible.