Flexible wings 2011

[FW17]

No wonder Mclaren were trying to get their wing to flex.


Thanks to Khan_F1 on twitter

[Raptor22]

thats just roll due to load transfer.

[horse]

No wonder Mclaren were trying to get their wing to flex.


Thanks to Khan_F1 on twitter

thats just roll due to load transfer.

I'm sure that the wing pillars are part of the magic here. They really allow the wing to pivot while being able to carry all of the load. I'm convinced this is one way RB get around the deflection tests where the wing is loaded symmetrically (I think).

You want the most force on the loaded wheel so let the wing pivot to generate the more downforce on the loaded side while sacrificing some DF on the unloaded side.

[Raptor22]

I don't folow. If it pivots how does it pass the load test?

A pivot is a frictionless device that allows articulation.


The red line I assume is too depict the curvature due to flex. Its clear that is a uniform curve across the span indicating that the entire span is flexing from about the point of suspension of the wing.
the wing can flex it just has to pass a load test.

As long as the car passes any static test it is legal.

[horse]

I don't folow. If it pivots how does it pass the load test?

A pivot is a frictionless device that allows articulation.

Yeah, sorry, my bad, the deflection test is asymmetric, so allowing the wing to pivot would not help. I still think it does pivot some though (about the centre line) and perhaps this aids the non-linear behaviour of the flex?

Some example pivot:

[FW17]

I still think it does pivot

If there is a pivot there is no way of controlling the deflection without a bulky restraining device which is absent (else would have been questioned by FIA)

[horse]

If there is a pivot there is no way of controlling the deflection without a bulky restraining device which is absent (else would have been questioned by FIA)

I take it back that the pivot would aid passing the deflection test, I had the wrong idea of how it was carried out. I still think some pivot is beneficial (and apparent in the above photo) and must be initiated/constrained by the action of the pillars.

[Raptor22]

I don't folow. If it pivots how does it pass the load test?

A pivot is a frictionless device that allows articulation.

Yeah, sorry, my bad, the deflection test is asymmetric, so allowing the wing to pivot would not help. I still think it does pivot some though (about the centre line) and perhaps this aids the non-linear behaviour of the flex?

Some example pivot:

Hmm I'm thinking its just a good photo that catches the wing at a moment of vertical deflection of the inside span. If the car ran over a bump the vertical deflection of the entire mass would result in some oscillation in the wing since it is not a well damped structure. I don't think we're seeing anything special in this picture. The wing certainly won't flex more on one side due to the cornering force since the wing span feels the cetripetal force parallel to the road.

[horse]

The wing certainly won't flex more on one side due to the cornering force since the wing span feels the centripetal force parallel to the road.

Yeah, I take on what you're saying about the picture, it could be a fluke, it's hard to disprove it, although you do see a lot of pictures of the RB with the wing "cocking" so to speak.

Regarding the centripetal force, yes, I see that that could push the wing away from the centre line. However, I think the wing can still flex more on one side because, as you pointed out, the car's set will tip the chassis + nose onto the loaded side which initiates an asymmetry on the wing as one side is now closer to the road. Now if the wing can flex and pivot further then that asymmetry will get more pronounced as the wing on the loaded side gets closer and closer to the road surface.

The caveat to this idea is what happens when the car straightens out? If my premise is true, how does the wing snap out of the asymmetry and return to level?

[shelly]

I suggest opening a new thread, "flexible wings controversy 2011" could be a name, for discussing the topic of flexible front wings (and their testing devices).

As a start we could summarize general trends in opinions from last year thread and try to move on from there.

[Raptor22]

The wing certainly won't flex more on one side due to the cornering force since the wing span feels the centripetal force parallel to the road.

Yeah, I take on what you're saying about the picture, it could be a fluke, it's hard to disprove it, although you do see a lot of pictures of the RB with the wing "cocking" so to speak.

Regarding the centripetal force, yes, I see that that could push the wing away from the centre line. However, I think the wing can still flex more on one side because, as you pointed out, the car's set will tip the chassis + nose onto the loaded side which initiates an asymmetry on the wing as one side is now closer to the road. Now if the wing can flex and pivot further then that asymmetry will get more pronounced as the wing on the loaded side gets closer and closer to the road surface.

The caveat to this idea is what happens when the car straightens out? If my premise is true, how does the wing snap out of the asymmetry and return to level?

What you are suggesting is an increase in wing flexure as the ground effect increases?
You could be right but I can't answer that without data on the wing.

[Mchamilton]

No wonder Mclaren were trying to get their wing to flex.


Thanks to Khan_F1 on twitter

thats just roll due to load transfer.

I'm sure that the wing pillars are part of the magic here. They really allow the wing to pivot while being able to carry all of the load. I'm convinced this is one way RB get around the deflection tests where the wing is loaded symmetrically (I think).

You want the most force on the loaded wheel so let the wing pivot to generate the more downforce on the loaded side while sacrificing some DF on the unloaded side.

during last years race at SPA, the BBC showed a comparison between the mclaren and the red bull as they took right handed of the final chicane. the mclaren wing flexed only slightly as the car bounced over the curbing, where as the red bull wing flexed a huge amount in 2 ways. the pillars "flexed" laterally (mainly from the point where they join the nose cone), and either side of the main plane of the wing flexed vertically from the point where they 'connect' to the FIA restricted centre section. i cant currently find a video of it, so if someone has a recording of that race from the BBC that would be useful to see what im saying.

[marekk]

The wing certainly won't flex more on one side due to the cornering force since the wing span feels the centripetal force parallel to the road.

Yeah, I take on what you're saying about the picture, it could be a fluke, it's hard to disprove it, although you do see a lot of pictures of the RB with the wing "cocking" so to speak.

Regarding the centripetal force, yes, I see that that could push the wing away from the centre line. However, I think the wing can still flex more on one side because, as you pointed out, the car's set will tip the chassis + nose onto the loaded side which initiates an asymmetry on the wing as one side is now closer to the road. Now if the wing can flex and pivot further then that asymmetry will get more pronounced as the wing on the loaded side gets closer and closer to the road surface.

The caveat to this idea is what happens when the car straightens out? If my premise is true, how does the wing snap out of the asymmetry and return to level?

What you are suggesting is an increase in wing flexure as the ground effect increases?
You could be right but I can't answer that without data on the wing.

Hard to tell about ground effect, but in corner (yaw) air speed (and downforce) is bigger on the outside part of the wind - exactly the same effect as pushing a ruder on airplane - one wing drops, the other goes up.

[Raptor22]

errm, I don;t think so. the difference is very very small this is not like a rudder its like doing a flat turn in a Zivko Edge 540. the outside wing does have a more airflow and is partly the reason why the plane will wnat to dip its inside wing (in a F1 car lift the inside wing), but its also the application of rudder that creates an imblanced force with a slight vertical componentthat pushes the inside wing down.

Its not the same scenario and the span on an F1 wing is much much less.

We're seeing the effect of a car not running rear springs. The rear suspension is much more supple than the fronts so the cars tend to roll on their rear axles, cocking the inside front wheel and the inside front wing span.

[volarchico]

We're seeing the effect of a car not running rear springs. The rear suspension is much more supple than the fronts so the cars tend to roll on their rear axles, cocking the inside front wheel and the inside front wing span.

And then throw in a bit of flexy-wing and that's the full story!