29 replies to this topic

[Turn 1]

I understand it is an attempt to minimise dirty air for a following car, but a simple explanation of how changing the angle of the front wing would be appreciated?

[scarbs]

The front wing flap angle adjustment was not to improve the turbulence behind the car, but simply to give the driver more front downforce to allow overtaking.
Only the flap element is allowed to move by no more than six degrees up and down each lap (it must return to the baseline position each lap), even the rate of angle change is controlled by the rules. It will take a few seconds to move the full 6 degrees, but most designers tell me it will be rare to use the full 6 degrees of movement.
The movement will be controlled by the driver, who will have a dial to select the angle change and a button to actually move the wing. The wing is moved by an electric motor inside the endplate, the power to get to the motor goes through wiring inside the wing and nose cone which then connects to the car (as the nose cone is removable) by a malefemale socket.


Scarbs

[Stefan_VTi]

I suppose all the extra rules were necessary to prevent the drivers from using them as brake flaps?

[wingwalker]

Originally posted by scarbs
(it must return to the baseline position each lap)

Is it in the rules? I though driver is allowed to change it 2 times per lap, but is free to decide when (so he can do 5 laps in a row with flap being in lowest/highest position if he wants to, he is only limited to 2 changes per lap).
I have doubts on how it's gonna work, could you write more about that?
I guess the ECU will make the flap go to baseline position when car crosses the line.. which could be a bit problematic: if it takes a few seconds, it's gonna do additional few seconds to move where the driver wants it, so on tracks with turn1 a short while after the end of sector 3 wing position can be somewhat compromised... or is it anywhere on the track and it will be driver responsibility to switch it before the finish line?

[Kalmake]

Do you think it will be used for other things than overtaking? Like decreasing the angle every lap for a faster section of a track.

[zac510]

Originally posted by Kalmake
Do you think it will be used for other things than overtaking? Like decreasing the angle every lap for a faster section of a track.

Most cynics think that's the only thing it will be used for.

[cheapracer]

Originally posted by Kalmake
Do you think it will be used for other things than overtaking? Like decreasing the angle every lap for a faster section of a track.

I can't understand why it's not simply brake specific operated stopping all of this nonsense. Simplistically put - touch the brakes, the wing dips (FIA'ed predetermined rate of speed), foot off and the wing returns.

[zac510]

Originally posted by cheapracer


I can't understand why it's not simply brake specific operated stopping all of this nonsense. Simplistically put - touch the brakes, the wing dips (FIA'ed predetermined rate of speed), foot off and the wing returns.

But then every driver would have the wing change when they're braking, all at the same time and the status quo will be maintained. I think you are thinking too much like an engineer . By putting the driver in control they're trying to create another possible difference in speed between one and another car, just like the instruction to Bridgestone to make the difference between prime and option tyres greater.

[imaginesix]

Originally posted by cheapracer
I can't understand why it's not simply brake specific operated stopping all of this nonsense. Simplistically put - touch the brakes, the wing dips (FIA'ed predetermined rate of speed), foot off and the wing returns.

Shorter braking zones make passing harder, your suggestion would contribute to the problem not alleviate it.

[primer]

Driver workload will increase dramatically this year! In addition to the usual duties, now they have to manage the application KERS and flaps as well. This is not good for safety.

[Stefan_VTi]

Yeah... those poor drivers, wouldn't want to trade with them...

[4ren]

How is the signal given to the front wing? Because if a new nose-cone is needed, it has to be easily changeable in the pits. So, is there a quick electrical connector? Or is it pneumaticaly activated?

[slideways]

scarbs won't they just set the default to maximum downforce, then 'trim down' for the longest straight?

[phantom II]

I can't imagine flying an aircraft with ailerons, spoilers, rudder and elevator taking a few seconds to move 6 degrees. That would be a death sentence. Even one second to move that F1 front wing flap 6' is dangerous.
I didn’t mention flaps above in the list of control surfaces on the aircraft, because flap positions are usually predetermined settings, the angles of which will provide a specific 'performance' value. IE: Before your land and before you take off. Even then, the slow movement of the worm drive flap activation can get you into trouble, no matter the size of the airplane. IE: wind shear and emergency go arounds or missed approaches in high level storms. OK, if you have misjudged obstacle height at the end of the runway and need to prevent an accident in a hurry would be a good time to have instant flap activation.
Some aircraft have instant cable or push rod flap activation.
Spoilers, be they on 747, F4s or gliders, are instant activation, either with cable/pushrod or hydraulic for very good reason. Sometimes, they are deployed actively, or by levers, or by pilot or non pilot operated switches. (squat)
The flap on this new F1 front wing is used more as a control surface, therefore it should have instant activation or banned immediately. Would you like me to describe the scenarios that could occur that 'will' cause an accident caused by sluggish flap activation, or can you figure that out yourself?
Which F*+^%#@ AH thought that up? A f*&%#@?g knob on the steering wheel? FFS. What kind of a F*%# human beings are involved here? F*&^%$#g Communists?

Originally posted by scarbs
even the rate of angle change is controlled by the rules. It will take a few seconds to move the full 6 degrees, but most designers tell me it will be rare to use the full 6 degrees of movement.
The movement will be controlled by the driver, who will have a dial to select the angle change and a button to actually move the wing.
Scarbs

[scarbs]

Originally posted by slideways
scarbs won't they just set the default to maximum downforce, then 'trim down' for the longest straight?

Its an option, but the front wing adds very little drag to the car, so there wont be a reasonable top speed gain by doing that. Teams use the front wing to balance the car, so the adjustment will be either to traim the balance a little or for alot more angle when following another car.

[phantom II]

The front wing produces 37% of the total downforce so it's primary function is not to trim the total aero package. The top element of the flaps will not only increase the camber of the wing but will also function as a trim element, which is normal except that it is now movable. I'm not sure what the total loss of downforce is on the car or even the front wing for that matter when it follows another. I would assume that the greatest loss would be on the front wing as a percentage. This temporary loss is partially or completely regained by driver input with the use of this trim function on the flap. If the car is able to make a pass, it would immediately become imbalanced and this could prove disastrous in a high speed turn or the effects of adverse braking bias in the braking zone for a tighter turn unless an instantaneous reset is achieved.
Maybe the front brake could have a larger accumulator to activate a flap actuator that is controlled by a button on the steering wheel.

Originally posted by scarbs

Its an option, but the front wing adds very little drag to the car, so there wont be a reasonable top speed gain by doing that. Teams use the front wing to balance the car, so the adjustment will be either to traim the balance a little or for alot more angle when following another car.

[slideways]

Webber's opinion after playing with the adjustable wing:

"I don’t see how that’s going to overtaking," he says of the latter. "It's like a little leaf going down in the ocean I think!"

[Bill Sherwood]

Originally posted by slideways
Webber's opinion after playing with the adjustable wing:

"I don’t see how that’s going to overtaking," he says of the latter. "It's like a little leaf going down in the ocean I think!"

.... and then the car broke.

I'd much rather see the cars without such devices, less to go wrong and fiddle with.

[desmo]

This idea is obviously the product of a mediocre intellect and imagination. Simple plan area limits outside the wheelbases would be far more effective.

[kilcoo316]

Simple concept.

It is supposed to compensate somewhat for the understeer that exists due to the wake of the car in front.

As others have said - the front wing doesn't cause much drag compared to the rest of the car, so adjusting it through a lap for extra speed doesn't make sense... minor adjustments for balance reasons might be worthwhile.



The FIA finally realised that moving the wing closer to the ground ensures less turbulence, and also a more consistent incidence angle onto the wing - hence why they reversed the utterly stupid decision to raise the front wing height (twice).


Reducing the diffuser size should also help reduce the wake upwash near the ground.

[Frederic]

Originally posted by kilcoo316


... moving the wing closer to the ground ensures less turbulence, and also a more consistent incidence angle onto the wing ....

Why will there be less turbulence?

Why is the incidence more consistent?

Moving the wing closer to the ground has the potential to increases front wing loading because you are moving more into ground effect but this does not necessarily make the car easier to drive. Ground effect front wings are more susceptible to ride height and reynolds number instabilities. For a given front wing increasing the stress on the elements will also result in increased yaw and steer instabilities.

[kilcoo316]

Originally posted by Frederic
Why will there be less turbulence?

Because the close proximity of the ground plane damps all the larger eddies. Smaller eddies have a smaller effect on the wing's performance.

Originally posted by Frederic

Why is the incidence more consistent?

Because by definition, there can be no velocity normal to the ground at the ground. The closer you get to the ground, the less pronounced the velocity normal to the ground will be.

Originally posted by Frederic

Moving the wing closer to the ground has the potential to increases front wing loading because you are moving more into ground effect but this does not necessarily make the car easier to drive.

The wings are already deep into wing ground effect - if I recall right, wing ground effect becomes pronounced at anything under half wingspan from the ground.

This is different from underfloor ground effect - it is related to the two trailing vortices.

Originally posted by Frederic

Ground effect front wings are more susceptible to ride height and reynolds number instabilities.

As they may experience a sharp stall... however they aren't even close to that regime as they aren't even close to being low enough for that to occur.

The effective exit to effective throat area ratio is not near large enough to stall out.

Originally posted by Frederic
For a given front wing increasing the stress on the elements will also result in increased yaw and steer instabilities.

Which is, as you say, the case regardless of where the wing is positioned relative to the ground. Run a more aggressive front wing angle, and you get the same problems.

[Frederic]

Originally posted by kilcoo316


Because by definition, there can be no velocity normal to the ground at the ground. The closer you get to the ground, the less pronounced the velocity normal to the ground will be.

What do you think the velocity profile looks like?

[kilcoo316]

Originally posted by Frederic

What do you think the velocity profile looks like?

I know what the modulus of the vertical velocity profile will look like.

Without knowing the detailed turbulence fluctuations, I cannot predict the instantaneous velocity profile - even then, it will only be relevant for an instant.

It is basically of similar shape to a Blasius boundary layer profile.



While, on track, in reality, the tangential surface flows on the car and road have Sakiadis profiles representing the boundary layer.


So to recap (for a car on track) -

Sakiadis - this does not apply to the road, only the moving vehicle.

Blasius - this applies to the normal on both car and road, as well as the tangential on road.

[Frederic]

Originally posted by kilcoo316


I know what the modulus of the vertical velocity profile will look like.

Without knowing the detailed turbulence fluctuations, I cannot predict the instantaneous velocity profile - even then, it will only be relevant for an instant.

It is basically of similar shape to a Blasius boundary layer profile.



While, on track, in reality, the tangential surface flows on the car and road have Sakiadis profiles representing the boundary layer.


So to recap (for a car on track) -

Sakiadis - this does not apply to the road, only the moving vehicle.

Blasius - this applies to the normal on both car and road, as well as the tangential on road.

What boundary layer? Are you referring to wind gusts?

The incident velocity is not dependent on the height from the ground.

[kilcoo316]

Originally posted by Frederic

What boundary layer? Are you referring to wind gusts?

It (the velocity normal to the ground) has the profile shape of a boundary layer - that does not make it a boundary layer.

Originally posted by Frederic

The incident velocity is not dependent on the height from the ground.

Yes it is.


Air cannot pass through the ground - and it cannot decelerate instantaneously. Therefore, the potential* velocity normal to the ground is very much dependent on the distance from the ground.


*Potential = is a function of 'freestream' momentum and any pressure gradient normal to the ground.

[Frederic]

Originally posted by kilcoo316






Air cannot pass through the ground - and it cannot decelerate instantaneously.

How is the air accelerating or decelerating anywhere? It is the object that is moving. What forces are acting which would give this deceleration?

[kilcoo316]

Originally posted by Frederic

How is the air accelerating or decelerating anywhere? It is the object that is moving. What forces are acting which would give this deceleration?

I feel like I'm explaining something so obvious here.... An object causes the deceleration of any velocity which is normal to the object's surface - how can air flow through any solid object?

(you know normal means at 90degs to the ground plane yes?)



OK, lets go over it again:

The car in front induces vertical velocities within its wake - these are real velocities - and are non-zero.

The nearer you are to the ground, the less pronounced these vertical velocities will be (throughout the wake) due to the inability to have a velocity normal to the ground at the ground.


As I said in my first post - having the front wing lower means a more consistent incidence angle as there can be less vertical velocity resulting from the wake of the car in front.

As well as reducing the size of the eddies (which induces other problems).

[Powersteer]

Originally posted by scarbs
The front wing flap angle adjustment was not to improve the turbulence behind the car, but simply to give the driver more front downforce to allow overtaking.
Only the flap element is allowed to move by no more than six degrees up and down each lap (it must return to the baseline position each lap), even the rate of angle change is controlled by the rules. It will take a few seconds to move the full 6 degrees, but most designers tell me it will be rare to use the full 6 degrees of movement.
The movement will be controlled by the driver, who will have a dial to select the angle change and a button to actually move the wing. The wing is moved by an electric motor inside the endplate, the power to get to the motor goes through wiring inside the wing and nose cone which then connects to the car (as the nose cone is removable) by a malefemale socket.

Well, if the front wing was spring loaded to move 6 degrees or even more, without any eletro hyraulic aid, it would naturally become steeper slipstreaming from the lack of air force making good compensation while return back to its original load on laminar air flow. It won't work on slower parts of a circuit but that would be less aerodynamic dependant areas. So much more simpler, without any electro-triggering cost cutting devices! I guess the spring load can be changed to suit an effective area of the track.

[Ogami musashi]

Scarbs: I think the 09 regs still make balance shifts quite sensitive especially on the front wing. So i think the flap would be for balance more than downforce increase.

Of course could be used for that also.


As far as the low front wing reason, it was just because of its relative position to the turbulences wash.

The fact it runs more in ground effect has improved the freestream downforce generation (renault even had more downforce on front than they wanted compared to the rear wing aviable) but as far as wake performance is concerned, for a given turbulence pattern the performance doesn't change that much. It is really a question of location of both elements (front wing relative to wake).