ringo wrote:
Multi elements will always have more down force. The closer the wing is to the ground, the better down-force it should have.
Up to a point, yes, but a multi element wing will be better than a plane + flap as at present as it gets near the ground.
They can't be that bad at engineering, that they create a wing that stalls with one or 2 degrees of pitch.
They would have to be over estimating Reynolds numbers in the wind tunnel if that were the case.
Maybe that is the problem. After all, McLaren found that they had some tunnel errors (or at least correlation between tunnel and CFD) and they're somewhat more experienced than Merc are.
The wing is probably an issue, but i wouldn't single it out. It's also a popular thing to say it affects everything behind it and a new one with change everything. I think that only held true back in the days when front wing designs weren't as converged as today. Most all the wings on every car on today's grid have very similar wake patterns.
The end plates are more critical to what's behind the car i believe.
The wing as a whole affects the whole car behind. Sure, the endplates are very powerful but to dismiss e.g. the effects of a stray vortex from the main part of a wing is a little shortsighted. If they are struggling to keep the flow attached to the front wing then they will have a whole-car problem once separation occurs.
So i have a suspicion the team may have some misguidance with concepts all over the car. And it's the slightly misguided interpretations of key elements of the car that culminate into a car 1 second off the pace.
Well of course they have little issues all over thr car that reduce their ultimate pace. All cars do - even the RB7 won't be perfect...
Last edited by mx_tifoso on 06 Mar 2011, 03:49, edited 1 time in total.
Reason:Posts split from W02 thread.
If you are more fortunate than others, build a larger table not a taller fence.
why would a multielement always give more downforce? I always thought this was a matter of being able to have more wing inclination before suffering separation..but the front wing array has a maximum height so it seems there is a penalty to pay for using a three(or more) element wing ,drag ,perhaps?
marcush. wrote:why would a multielement always give more downforce? I always thought this was a matter of being able to have more wing inclination before suffering separation..but the front wing array has a maximum height so it seems there is a penalty to pay for using a three(or more) element wing ,drag ,perhaps?
As for basic aero rules, drag increases with more cross section, so to reduce the cross section we have multiple elements wing......so single element and same sized multiple elements have same Downforce, but the muti element has less drag
Thats why FIA reduced the rear wing to 2 elements so that they can increase the drag but still having the same downforce.
marcush. wrote:why would a multielement always give more downforce? I always thought this was a matter of being able to have more wing inclination before suffering separation..but the front wing array has a maximum height so it seems there is a penalty to pay for using a three(or more) element wing ,drag ,perhaps?
As for basic aero rules, drag increases with more cross section, so to reduce the cross section we have multiple elements wing......so single element and same sized multiple elements have same Downforce, but the muti element has less drag
Thats why FIA reduced the rear wing to 2 elements so that they can increase the drag but still having the same downforce.
correct me if i am wrong here guys
Multi-element front wings are not used to reduce drag with respect to a double-element section.
They may be more effective in managing the pressure gradient that comes fromm the presence of front wheels behind the wing.
With the new regulations from 2009 the importance of the front wing is higher than before, and not only beacuse it is bigger: the ban of big barge boards implies that the vortex structures created by the front wing impact more directly on the tea tray and floor.
A wing producing a bad pattern ruins the floor on the whole underbody; on the positive side , a very good front wing would benefit all the car.
In my opinion, with the current regulations, it is reasonable to expect big gains in term of laptime comeing from just a new, more efficient front wing.
n smikle wrote:I hope maximising the pull rod is on the list of changes. Notice that it angled too far bacwards, interrupting the flow near the beam wing. They also need to raise up the beam wing; make it a floating design like redbull and willliams. Just a few things I think can make a difference.
The problems probably start well in front of that area. The front wing is likely to be an issue and this then affects everything behind it.
I've seen suggestions that the front wing is, in effect, stalling (they appear to be struggling to keep the flow attached). Indeed, there appear to be problem with both drivers getting the nose to do what they want in to corners which suggests the thing might be struggling to stay attached as it gets closer to the ground under braking (assuming the thing gets much dive in such circumstances). This is why they had some faitly crude cut outs in the front wing at the last test. They need to run a multi-element front wing. A single flap as at present can give higher downforce in theory but it is much more difficult to keep the air flow clean. Better to run a theoretically less powerful multi-flap wing which actually works. Get that right and then you can get the airflow to the rear sorted.
Multi elements will always have more down force. The closer the wing is to the ground, the better down-force it should have.
I agree that they need to run a multi element wing, but i don't think it's because the current one is stalling. Maybe the efficiency drops considerably.
They can't be that bad at engineering, that they create a wing that stalls with one or 2 degrees of pitch.
They would have to be over estimating Reynolds numbers in the wind tunnel if that were the case.
The wing is probably an issue, but i wouldn't single it out. It's also a popular thing to say it affects everything behind it and a new one with change everything. I think that only held true back in the days when front wing designs weren't as converged as today. Most all the wings on every car on today's grid have very similar wake patterns.
The end plates are more critical to what's behind the car i believe.
Looking at the car now, it can be seen that things like the blown exhaust seem aimlessly designed. They are blowing into the floor not along it.
Then looking on the bulky roll hoop and engine cover. You have the internal channel where the radiator exhausts up and over the engine and out the back. We don't know how well this channel is designed, how the oil coolers interact with this, or whether the roll hoop should have done better with a cooling hole underneath it.
Then looking on the rear uprights, on the high and sloping upper control arm links. Why are they so high and to what effect?
Their degradation and hence overall pace could also be tied into their suspension design.
So i have a suspicion the team may have some misguidance with concepts all over the car. And it's the slightly misguided interpretations of key elements of the car that culminate into a car 1 second off the pace.
For a given plan area, a multi element wing theoretically makes less downforce because of less surface area. simple as that.Extra slot gaps take up room that could be used for producing downforce, but they also greatly reduce seperation on backside of wing hence they stall less.
“To be able to actually make something is awfully nice”
Bruce McLaren on building his first McLaren racecars, 1970
“I've got to be careful what I say, but possibly to probably Juan would have had a bigger go”
Sir Frank Williams after the 2003 Canadian GP, where Ralf hesitated to pass brother M. Schumacher
@Piece89: a three element wing has actually more area than a duoble element wing.
Leading and trailing edges of the elements are slightly superimposed, so you will see no slot if you look from above/underneath.
The slot is only visibel in frontal view
Pierce89 wrote:For a given plan area, a multi element wing theoretically makes less downforce because of less surface area. simple as that.Extra slot gaps take up room that could be used for producing downforce, but they also greatly reduce seperation on backside of wing hence they stall less.
Sorry, but it is not that simple. Airfoils do not generate lift equaly on whole surface. In fact, working near stall angle, 90% of lift is generated from 50% of wings surface.
Agree with mareek.
Downforce on wings comes in most part from leading edge suction peak.
Putting in fresh air in the flow on the lower part of the wing trough the slot allows for more aggressive pressure recovery (i.e. more aggressive transition from low pressure on the leading edge to near ambient pressure), Also you add some bockage on the upper surfae, so you raise the pressure on the top surface of the main element
sorry guys if it were that simple why on earth would it take years to go from 1 plane to multiple plane wings.
Ferrari were the first to introduce more than one flap on each side of the front wing if I´m correct and it took the rest of F1 quite a while to follow that route..
so to say more flaps is better per se cannot be universally true.And please explain why 3 flaps won´t be even better going along that logic?
@marcush: the point is that is not that simple. There are more aspects to take into account:
-legality box
-construction issues
-pitch sensitivity
-boundary conditions (e.g. relative position of wheels)
-effect downstream
-regulation and optimization issues
So for a long time it has seemed to the majority of teams that two element front wings gave the best compromise. New regulations, and finer cfd tools, have moved the tradeoff point.
Ferrari itself, after introducing a three element wing in 1995 IIRC, has gone back and forth on this solution, sometimes using it, sometimes not.
If you want to go deeper in the subject, there are plenty of references to cascade wings in literature, as this is a theme relavant also to landing configurations of airplanes.
marcush. wrote:sorry guys if it were that simple why on earth would it take years to go from 1 plane to multiple plane wings.
Ferrari were the first to introduce more than one flap on each side of the front wing if I´m correct and it took the rest of F1 quite a while to follow that route..
so to say more flaps is better per se cannot be universally true.And please explain why 3 flaps won´t be even better going along that logic?
3 flaps would be better, and 6 even more:
But as mentioned by shelly, there's far more to this, than simply downforce generated.
For example airfoils do change downstream flow a lot:
the main advantage of a multi element front wing is that it will stall later. The flow stays more easily attached to a smaller foil at high speed, so having three small foils instead of two big foils helps with that.
Hence the understeer problem of the Merc in high speed corners, as it sports a two-element front wing. The wing is possibly partly stalled in such a situation, leading to a loss of downforce at the front of the car, leading to understeer.
But this can also be beneficial. A stalled wing has massively less drag, as most of the "induced drag" disappears (the drag "caused" by the downforce the wing creates, as opposed to simple friction and displacement drag, is called "induced drag"). That's the principle of the McLaren F duct, but on the front wing if you will. And that in turn brings a higher top speed.
Also, generally, when the flow is attached on both, a two element wing will have lower drag than a three element one, becuause
a) it has less "skin" exposed to the flow than a three element wing, so has lower "friction" drag
b) it seems thinner in the flow than a three element wing, because there is only the thickness of two elements that stand in the way of the flow instead of three.
c) three foils will always create more wake vortices than two, and that will impact the rest of the car.
so a three element wing will bring better stability of the downforce, especially at high speeds or when big attack angles or speed angles are applied (like under braking for example), because the flow will stay attached more easily. So the downforce is not notably bigger, but it is more constant.
However, it comes at the cost of greater drag, especially at high speeds, and a more unsteady flow to the back of the car.
Unless I am missing something, the drag of an F1 wing has relatively little to do with the frontal cross section (more or less equal in all cases) and skin drag and the such. F1 wings do not work like plane's wings, witness the almost vertical fences that we call rear wings.
These wings are designed to capture as much air as possible, and push upwards not only the air they cross, but, as much as possible, they try to capture air around them and send it upwards too. A wing affects air well beyond its cross section. The more air yo send upwards, and the faster upwards you send it, the more downforce you get.
Now, it is not like the wings are magically creating upwards thrust in the air like a rocket, they capture air moving horizontally relative to the wing, and send it out as vertically as possible. The total speed of this air (relative to the car) is not going to increase, and hence, air sent upwards has been redirected more than anything else and has lost most of its horizontal velocity.
All that air sent upwards in the name of downforce is being stopped horizontally, that is, pushed forwards, that is, the car has been pushed backwards, that is: drag.
So to me, in a good and efficient design, the more downforce you make, the more drag you will have. Because, except from the diffuser, this downforce comes from slowing air to send it upwards. That's why a stalled wing has less drag, as it has stopped pushing air upwards, it also has stopped decelerating it horizontally.
As far as I know, a three element wing (an efficient one), simply manages to capture more air and expel it at a more vertical angle than a two element wing.
marcush. wrote:sorry guys if it were that simple why on earth would it take years to go from 1 plane to multiple plane wings.
Ferrari were the first to introduce more than one flap on each side of the front wing if I´m correct and it took the rest of F1 quite a while to follow that route..
so to say more flaps is better per se cannot be universally true.And please explain why 3 flaps won´t be even better going along that logic?
designing wings is not simple(news flash)What is simple, is understanding two planes in a given plan area can have more surface area than three so theoretically can produce more downforce. That's all I said was simple. Pure and simple.
“To be able to actually make something is awfully nice”
Bruce McLaren on building his first McLaren racecars, 1970
“I've got to be careful what I say, but possibly to probably Juan would have had a bigger go”
Sir Frank Williams after the 2003 Canadian GP, where Ralf hesitated to pass brother M. Schumacher
