I think you 're getting confused in the terminology ... linear flex doesn't mean that it flexes in a straight line, linear flex means the amount of flex increases proportionately to the force applied. I m not seeing the drinking straw parallel here.

I m not sure how to explain this in very very simple terms ... forget carbon fiber and wings and elasticities.

Imagine you have two scales and a random amount of weights.

you put 1 5lbs weight on each scale, they both show 5lbs. You put a second 5lbs weight on each scale, the one scale shows 10lbs (that's linear flex) the other scale shows 18.5lbs (that's non linear flex)

Flex on the wing is the vertical movement on the wing from its rest state. Assume the wing was a perfectly straight horizontal line. Say you attached a 50kg weight to one end of that straight line and saw that particular end move downward by 10mm. That's the flex of the wing, those 10mm with 50kg load. That wing is said to flex linearly if you add a second 50kgr weight to the same side of the wing and measure it to see that it has now moved 20mm downward from it's perfect horizontal line. Non linear would be any amount of movement except that.

My Brother is an Engineer and i was talking to him about F-1 latest drama and he happen to mention you can get an object to flex by applying opposing forces,probaly stating the obvious but in the case of a car wing upwards pressure as well as downwards and all the associated effects in between, anyway point being i think Newey is on to something that could take years for the lesser teams to match without a regulation change.

No, I understood that. Either you're not getting what I'm saying, or what I'm saying is not correct and a straw would not flex non-linearly.

I thought a straw, as you make it flex, there is not only the material flexing but also the circle (of the shape extruded) changing to an oval, and as the more you flex it, the more "oval-like" it gets...

Now as the more "oval-like" the shape it gets, the easier it is to flex it, understand what I mean?


ps: my really bad english doesn't help either

No, I understood that. Either you're not getting what I'm saying, or what I'm saying is not correct and a straw would not flex non-linearly.

I thought a straw, as you make it flex, there is not only the material flexing but also the circle (of the shape extruded) changing to an oval, and as the more you flex it, the more "oval-like" it gets...

Now as the more "oval-like" the shape it gets, the easier it is to flex it, understand what I mean?


ps: my really bad english doesn't help either

What is a 'point' of downforce? I heard them use the term on SpeedTV, and I wasn't sure what it meant. Is it a percentage of the car's weight? 100 kilos? 10 stones?

My Brother is an Engineer and i was talking to him about F-1 latest drama and he happen to mention you can get an object to flex by applying opposing forces,probaly stating the obvious but in the case of a car wing upwards pressure as well as downwards and all the associated effects in between, anyway point being i think Newey is on to something that could take years for the lesser teams to match without a regulation change.

I think I get what you are saying. As the straw deforms (changes from a circle to an oval and then to a very thin elipse) the nature of its elasticity changes.

This though is only because the composition of the straw changes (air has escaped).
What if both ends of the straw were sealed airtight?

I believe they were testing both types of front wing to assess what their effects are on the new updates as they are expecting some new rulings around the front wing for Spa.
Simply adopting the boy scouts motto of "be prepared".

Interesting that the FIA is looking to change the rules on the front wing and yet they didn't do the same thing on the F-Duct concept. I'm sure they have their reasons for this however if it had been another team with the F-Duct concept, say Ferrari, and the same outcome ensued i wonder if this would have been seen as some sort of favouritism?

I'm against a rule clarification mid season simply because it disadvantages those teams who have come up with ingenious solutions. It is this type of rule tampering that can effect the outcome of a championship. For all the comments from the FIA around fixing races, surely the FIA tampering with the rules can be seen as affecting and in some cases fixing a championship, at least to try and make it more competitive.

Many rules the FIA have brought in were done in the interests of slowing down a team that was doing better then the rest simply to spice up the show. I can't help but feel this is the same thing. RB have done a great job, they should be rewarded for it, not penalised.

The point system is another prime example, it was changed to stop Schumacher and Ferrari dominance, and has been changed yet again now that the playing field is more level to promote overtaking and not settling for 2nd position.

It is a joke. Winning a title is becoming more about timing of a cars development and luck being on your side with respect to the FIA and the way they manage the regs during that season.

If McLaren had found a quick fix to the flexi wing and could develop it themselves there would not be a call for a rule change by them; they dont understand how to implement it because of their engineering incompetence in this area and instead want a rule changed to favour them. Should the FIA comply with their request then i wonder if the question would eb asked as to whether the FIA is working in McLarens interests and is favouring them instead of the usual comment that the FIA and Ferrari are hand in hand?

Just to remind people, rule 3.7.1 is in play as well. It is assumed the 75mm is " at all times".

Many rules the FIA have brought in were done in the interests of slowing down a team that was doing better then the rest simply to spice up the show. I can't help but feel this is the same thing. RB have done a great job, they should be rewarded for it, not penalised.

The point system is another prime example, it was changed to stop Schumacher and Ferrari dominance, and has been changed yet again now that the playing field is more level to promote overtaking and not settling for 2nd position.

If McLaren had found a quick fix to the flexi wing and could develop it themselves there would not be a call for a rule change by them; they dont understand how to implement it because of their engineering incompetence in this area and instead want a rule changed to favour them. Should the FIA comply with their request then i wonder if the question would eb asked as to whether the FIA is working in McLarens interests and is favouring them instead of the usual comment that the FIA and Ferrari are hand in hand?

Should the FIA comply with [McLaren's] request then i wonder if the question would eb asked as to whether the FIA is working in McLarens interests and is favouring them instead of the usual comment that the FIA and Ferrari are hand in hand?

It is inconceivable that the d/f gain from a droop of 1mm from a starting point of 75mm is worth the same as 1mm from a starting point of 10mm.
The reason has become such a huge issue is the the Red Bull wings have began to skim the floor which it is believed is inducing ground effect.

Even looking back at Barceona (where Red Bull were fairly dominant) the wing tips were nowhere near the ground.

Interesting that the FIA is looking to change the rules on the front wing and yet they didn't do the same thing on the F-Duct concept. I'm sure they have their reasons for this however if it had been another team with the F-Duct concept, say Ferrari, and the same outcome ensued i wonder if this would have been seen as some sort of favouritism?

I'm against a rule clarification mid season simply because it disadvantages those teams who have come up with ingenious solutions. It is this type of rule tampering that can effect the outcome of a championship. For all the comments from the FIA around fixing races, surely the FIA tampering with the rules can be seen as affecting and in some cases fixing a championship, at least to try and make it more competitive.

If McLaren had found a quick fix to the flexi wing and could develop it themselves there would not be a call for a rule change by them; they dont understand how to implement it because of their engineering incompetence in this area and instead want a rule changed to favour them. Should the FIA comply with their request then i wonder if the question would eb asked as to whether the FIA is working in McLarens interests and is favouring them instead of the usual comment that the FIA and Ferrari are hand in hand?

There is a procedure in the rules for new flex tests being brought in (3.17.8) if certain criteria are met. The RB front wing, and the footage and pictures we have seen over the last couple of race weekends, clearly fit this criteria.

The FIA is simply following the rules. Doing so is not favouring McLaren, IMO.

I had assumed (earlier in this thread) that the combination of this rule and the fact the plank is 10mm below the reference plane means that the front wing end plates must be a minimum of 85mm off the ground.

I assume from the discussion on "rake" (Mandizpop - I'm with you, I had no idea what this meant a first!) that the reference plane can be at an angle to the horizontal surface on which the car sits? I also assume that this means that the reference plane at the point of the front wing can actually be beneath the ground? So rake can mean that the starting point for the FW end plates is actually less than 85mm off the ground?

One point of downforce (or drag) is equal to 0.01 Cl (or Cd) or in terms of actual Newtons of load 0.01 x 0.5 x Air Density x V^2 x Ref. Area, where the reference area is typically 1.5 m^2.

Ah, thanks, let me try a translation...

Cl = coefficient of lift. That's a ratio - the drag divided by the lift (or downforce in the case of a car). Multiply by 0.01 to get points.

So...if the drag is 1,000N and the d/f is 10N that's a Cl of 100; x0.01 = 1 point of downforce.

What's the drag on an F1 car at speed? They slow at >1g when coasting, that would make drag maybe 6,000N. So 1pt could be 60N at 300kmh.

25pts would be up to 150kg of d/f. Is that worth 1s a lap? Seems credible.

Any advance on that, anyone?

Yes, all F1 cars have positive rake, depending on suspension compression (and the actual camber on the road surface itself) the extension of the reference plane under the front wing can theoretically be "underground"

That's why I was saying that Martin's comment regarding the FW needing to be 85mm of the ground was inaccurate.

A simplistic explanation of rake is basically this ... imagine drawing a line at the bottom of the car, if that line goes towards the ground (meaning if generally the front of the car sits lower than the rear) then it's positive rake. If the line goes away from the ground (meaning the front sits higher than the rear) then it's negative rake.

You can get pretty good visual demonstration of rake from this McLaren MP4/25 launch photo .... follow the bottom of the car relative to the ground ... the imagine what happens if a) the ground itself was angled and b) if you have a stiff rear end suspension setup and a softer front end suspesion setup

yeah that's what I 've been saying, generate lift near the front wing pylons (basically lift the back end of the front wing) -> increases angle of attack (effectively) -> increases front wing load -> endplates drop down

Thanks engel

I don't think that rake alone can account for all of this, though. Although the difference with the RB FW is most dramatically exemplified by the fact it touches the ground, I still think the footage demonstrates a greater degree of movement in the wing itself. In bump event footage, for example, the RB wing seems a lot less rigid than the McLaren wing. I realise that bump events won't illustrate any performance advantage, but I think they give us an idea of inherent flexibility.

If the whole nose droops from the attachment point, the angle of attack will increase also.

There is something about that front wing attachment failing which surely points to this or 'something else' going on with the attachment.

I´m pretty sure you could observe the same effect in a vacuum (no air involved)

sealing the ends will not change much either, unless you pressurize the straw

the fact, that the straw/tube changes his shape during the application of a increasing load is the reason
for the change in stiffness

BTW how did we/some arrive at the conclusion that a FW is made from 100% carbon fibre ?

There are lots of different ways to achieve non-linear deflection, not least that the front-wing is not made only from carbon fibre and is, of course, not uniform.

Thanks engel

I don't think that rake alone can account for all of this, though. Although the difference with the RB FW is most dramatically exemplified by the fact it touches the ground, I still think the footage demonstrates a greater degree of movement in the wing itself. In bump event footage, for example, the RB wing seems a lot less rigid than the McLaren wing. I realise that bump events won't illustrate any performance advantage, but I think they give us an idea of inherent flexibility.

Have a look at the McLaren image posted.

Now imagine the same car with no rake, yet the wing still at the same level above the ground at standstill.

Now give that 'imagined' car the same (or slightly more) rake as the McLaren and imagine how close the front wing would be to the road.

I believe that is what Red Bul have achieved.

Remember the plank stops well short of the front axle line so it's not the issue everyone imagines it to be.

I would be thinking that the Red Bull has zero rake and more than the minimum ground clearance when stationary, and the wing is close to the minimum height in that configuration.

At speed, the front suspension compresses down, the rear stays the same and the front wing magically appears to be scraping the ground.

I don't suppose anyone has a side on image of the Red Bull without the driver in Parc ferme from a recent GP (preferably Hungary)?

I might do a computer edit of the McLaren when I get home to test the theory.

So we're back to ride height then?

So we're back to ride height then?

So the rear has no suspension travel despite literally tonnes of downforce acting on it?
It would have to be totally solid. The car would be undriveable.

Plastic has a linear elasticity, same as carbon fiber, right? When you get a plastic drinking straw and you bend it by where you're not supposed to (let's say the middle) it doesn't flex linearly because of its shape (the extruded circle). Is it possible to apply that to a front wing to make it flex non-linearly and depending of how the extrusion is made determine where will it stop flexing?

Thank you to everyone that are trying to explain this in terms that are far easier to understand. It does help.

An interesting point made in the print version of Autosport saying that CH has said that nothing is going to be changed on the RB6 as it will still pass the new tests. Also Ed Straw did a piece about the difference betweeen legal, not illegal and illegal cars. It is definately worth a read.

Interesting, Raziel.

The animated gif of the wing deflection posted a few days back almost looked like the nose was indeed moving slightly downwards and the failure of sebs new wing at silverstone may point to teething troubles with such a device. Couldve been the light though.

Hold something against the screen of your computer where the bodywork and suspension meet in the photo - wherever you like really, but just make a fixed point with a pencil which you can focus on. If you do, you'll see there's no movement along the bodywork and what you're seeing is the light change. I don't get the same result when I do the same with what looks to be the tip of the nose (or at least the visible part). There, the nose appears to dip very slightly.

I think Red Bull are on a slippery slope here..they only have themselves to blame if the fia clamp down on them..they have pushed the boundaries too far..

The Ferrari tea tray

http://twitpic.com/2btgkp

From another angle:

Perhaps a poor choice of words on my part, I wasn't expecting it to be disected sylable by sylable.

Perhaps better to say the rear end stays 'conventional' (ie normal F1 firmness from the first cm of travel) and the ride height drops only marginally with downforce as all the cars on the grid do.

Sure but if you actually do the calculations, the numbers just don't add up. For the centre of the front-wing to be within 30mm of the ground without the car bottoming is not feasible using only suspension movement as an explanation, at least not without a substantial increase in rake.

Whitmarsh alluded to the same thing when interviewed in Hungary

quote
You could explain it by hugely raked cars but if you just do simple geometry, then the ride height is going to be over 100mm and there is no evidence of that being the case. Or else, by some means the outer edge of those wings is lowering down more than we would expect or the front of the floor is moving up more than we would expect, because that is not a piece of bodywork that's meant to be rigidly attached.
unquote

Excuse me for being a bit stupid with this (I admitted that last night). Would the amount of fuel in the car affect that? I take it that the cars are tested with no fuel in them.

I think it's above a reference plane on the car (the bottom of the plank) so fuel weight doesnt affect this?

Fuel does affect it, that's why RB is proportionately so much better in quali trim than in race trim.

Excuse me for being a bit stupid with this (I admitted that last night). Would the amount of fuel in the car affect that? I take it that the cars are tested with no fuel in them.