Dirty air sensitivity and regulations

[PlatinumZealot]

Also, ground effect aero has been fased out for obvious reasons. It's terribly unstable and just not reliable enough to be deemed safe.

They were. In the seventies!

Those ground effect mechanism were rudimentary and crude if you ask me. Jammed skirts, stalled tunnels... bottoming out.. lol

If the present day experts had another look at ground effects the mind wonders the plethora of improvements that can be made with computer aided design and modern electronics.

The pagani Hyara and the La-Ferrari are good examples of mild, safe ground effects. Formula 1 appropriately will have more extreme interpretations. I figure the rules will have to be written to ensure saftey in all circumstances something akin to the DRS fail safe they have in place. Not really sure how they would do it.. but possible start out without any skirts.. a fan or two... or something..

[horse]

It is interesting because the problem is double faceted, both it terms of turbulence generation from the lead car and the downforce generation of the following car.

I believe ground effect cars generate a lot of turbulence, but the generation mechanism of following cars is not effected very much by this as the generation zone relies on air that is very close to the ground.

Indeed the front wing of a modern F1 car can be said to be in ground effect, and so should be less effected by the forward car's wake, but, unfortunately, they had to reduce the width of the wing because of all them punctures.

Assuming the rest of the car is sensitive to the turbulence of the leading car then it might be that perhaps regulated downforce reduction has had a negative effect. If the rear wing assembly is very strong then perhaps all the turbulent air is ejected vertically out of the way of trailing cars, whereas maybe now it is weaker more turbulent air is being directed at the cars behind.

Another thing to think about is that if I was an F1 designer, I might well be trying to upset the air behind my car deliberately and that perhaps some of the little generators we see might not be for the benefit of the host car at all.

[Andres125sx]

I´ve heard that for a way longer period. Even on Bridgestone era, when tire degradation was not an issue, they complained about dirty air. The only difference is now with tire degradation drivers cannot chase a car close enough because of the dirty air AND if they try for too long they´ll ruin their tires. With hard bridgestone tires they could try it for the whole race, but they also had many problems to keep close to the car in front

So it´s a problem of both dirty air and tire degradation. Ironically tire degradation was introduced to compensate the dirty air problem, so there was strategic differences to allow some overtakes and compensate the lack of because of the dirty air problem.

This dirty air is a by-product of a high-downforce open wheel formula.

The amount of trouble you have following another car is directly proportional to the amount of aero dependance those cars have.

True, but not completely accurate. There are some ways to generate downforce wich do not affect the car behind that much. Ground effect, fan cars, studied airfoiled wings (instead of flat ones) wich would generate less downforce but also will reduce turbulence...

The bold part pretty much confirms Moose's post. dirty air is for a large amount proportional to the dependency they have on aero.

Also, ground effect aero has been fased out for obvious reasons. It's terribly unstable and just not reliable enough to be deemed safe.

First, as Platinum Zeloat said, the unreliability of ground effect was 40 years back, I´d like to think in 40 years engineering has evolved enough.

Active wings were also banned because of safety reasons, today we see DRS wich is some sort of active wing, and it´s safe. Today, and specially from 2017 with the return of active suspensions wich keep a constant distance with ground, ground effect could be perferctly safe


Second, yes dirty air is a by product of downforce, but...

Another thing to think about is that if I was an F1 designer, I might well be trying to upset the air behind my car deliberately and that perhaps some of the little generators we see might not be for the benefit of the host car at all.

Also, problem is drag is not that a big of an issue for a car, and it´s drag what causes dirty air/turbulence, it obviously reduce top speed, but on cars any downforce increase surpass the consequent drag inconvenient, so engineers try to make wings to produce as much downforce as posible, and they don´t care about drag.... too much, they will obviously try to reduce it and produce an efficient wing, but if they have to choose between high downforce and high drag or both low, they will always choose the first one, wich derails to wings producing lots of turbulence and dirty air

See this picture:

First airfoil is the one producing highest lift/downforce level, but also highest drag. It´s used on some ultralights as their flying speeds is low and drag is not a big issue, so they only worry about lowering stall speed as much as possible wich is done increasing lift. But that´s not a good airfoil for high speeds (>150km/h) because of the high drag. Second airfoil produce a lot less lift, but also less drag and turbulence so it´s more appropiate for faster planes.

F1 does not follow this basic rules, they use first airfoil, and they use it for speeds in excess of 300km/h, what would be crazy if it was a plane, but they don´t care about drag that much so they use the airfoil wich generate the highest downforce no matter how much drag it produce

I´d change this, force them to use cambered wings instead of flat ones to reduce drag and turbulence, also downforce but this can be compensated removing some restriction, and there are some dozens to choose, so it´d be perfectly posible to reduce drag without reducing downforce

For example, allow ground effect and force them to use cambered wings. Same downforce, less turbulence

instead of solving the root of the problem (aero) they´re putting some patches trying to compensate or cover up the real problem.

They can't magically make it easy to follow a high downforce car. Those abilities have it's limits. Dirty air(which simply is turbulence) is a by product of downforce.

Yes they can as I´ve just explained, downforce is not generated only by wings. Another example, allow blown diffussers and reduce wing size, downforce remain constant but turbulence is reduced

[FrukostScones]

wasn't this supposed to be the solution from technical working group back then :

[wesley123]

First, as Platinum Zeloat said, the unreliability of ground effect was 40 years back, I´d like to think in 40 years engineering has evolved enough.

To a certain extent, sure. However, the laws of physics don't change. The same dangers are still present.

Active wings were also banned because of safety reasons, today we see DRS wich is some sort of active wing, and it´s safe. Today, and specially from 2017 with the return of active suspensions wich keep a constant distance with ground, ground effect could be perferctly safe

I'd say active wings aren't all that dangerous, the only issue comes when the valve/whatever stops working.

Also, keeping a constant distance to the ground is a fun thing, what about the curbs? That sure would change the position sufficiently to upset the ground effects.

When you'd allow active suspension you'd just end up with the teams making overly agressive ground effects aero because that's the only position they have to make it work. Which will be great when this setting would be somewhat upset, which brings it all back to the original problem of ground effects; It's too unstable.

Second, yes dirty air is a by product of downforce, but...

Another thing to think about is that if I was an F1 designer, I might well be trying to upset the air behind my car deliberately and that perhaps some of the little generators we see might not be for the benefit of the host car at all.

I don't see why people keep using that argument. It's pretty dumb, since that extra turbulence would impact your own aero just as much.

Also, problem is drag is not that a big of an issue for a car, and it´s drag what causes dirty air/turbulence, it obviously reduce top speed, but on cars any downforce increase surpass the consequent drag inconvenient, so engineers try to make wings to produce as much downforce as posible, and they don´t care about drag.... too much, they will obviously try to reduce it and produce an efficient wing, but if they have to choose between high downforce and high drag or both low, they will always choose the first one, wich derails to wings producing lots of turbulence and dirty air

Teams have power to overcome drag penalty, so whatever rule change would be proposed wont change much, as teams aim for max downforce anyways, which in turn brings back the dirty air.

See this picture:
https://encrypted-tbn1.gstatic.com/imag ... pgVPufFFQt
First airfoil is the one producing highest lift/downforce level, but also highest drag. It´s used on some ultralights as their flying speeds is low and drag is not a big issue, so they only worry about lowering stall speed as much as possible wich is done increasing lift. But that´s not a good airfoil for high speeds (>150km/h) because of the high drag. Second airfoil produce a lot less lift, but also less drag and turbulence so it´s more appropiate for faster planes.

F1 does not follow this basic rules, they use first airfoil, and they use it for speeds in excess of 300km/h, what would be crazy if it was a plane, but they don´t care about drag that much so they use the airfoil wich generate the highest downforce no matter how much drag it produce

F1 uses the second wing, for as much as you can divide them in those three classes. The wings are highly optimized to bring the best downforce in incredible ranges of AoA.

I´d change this, force them to use cambered wings instead of flat ones to reduce drag and turbulence, also downforce but this can be compensated removing some restriction, and there are some dozens to choose, so it´d be perfectly posible to reduce drag without reducing downforce

You'll end up with teams just optimizing the whole package to suit their needs in a similar fashion again.

For example, allow ground effect and force them to use cambered wings. Same downforce, less turbulence

If only it was that simple.

instead of solving the root of the problem (aero) they´re putting some patches trying to compensate or cover up the real problem.

They can't magically make it easy to follow a high downforce car. Those abilities have it's limits. Dirty air(which simply is turbulence) is a by product of downforce.

Yes they can as I´ve just explained, downforce is not generated only by wings. Another example, allow blown diffussers and reduce wing size, downforce remain constant but turbulence is reduced

It can only be done so much, it's an effect of the drag created by the car. So to reduce turbulence, you'd need less drag. The only way to really force less drag through is to limit power, as then the drag can't be overcome so easily anymore. Which brings the next issue; People don't like F1 with 400bhp engine packages.

[Moose]

wasn't this supposed to be the solution from technical working group back then :


http://www.google.de/url?source=imgland ... Pg8G8ghYyQ

Actually, that's not such a terrible idea - it forces the teams to design rear wings that work in dirty air, because they will always be in dirty air.

[Andres125sx]

First, as Platinum Zeloat said, the unreliability of ground effect was 40 years back, I´d like to think in 40 years engineering has evolved enough.

To a certain extent, sure. However, the laws of physics don't change. The same dangers are still present.

Obviously, but there´re new technologies to solve those dangers, active suspension is the most significant for this case as it can keep the gap constant easily

Also, keeping a constant distance to the ground is a fun thing, what about the curbs? That sure would change the position sufficiently to upset the ground effects.

When you'd allow active suspension you'd just end up with the teams making overly agressive ground effects aero because that's the only position they have to make it work. Which will be great when this setting would be somewhat upset, which brings it all back to the original problem of ground effects; It's too unstable.

Curbs are the same now, we´ve seen some accidents due to some car jumping and loosing tire contact with asphalt. Maybe it would be a solution to stop them using curbs too much, with ground effect they simply would need to avoid curbs completely...

Anycase ground effect was just an example, if too dangerous there´re many more banned technologies wich may be allowed to compensate the reduction in downforce with wings that does not produce so much dirty air

Teams have power to overcome drag penalty, so whatever rule change would be proposed wont change much, as teams aim for max downforce anyways, which in turn brings back the dirty air.

Agree, but if they´re forced to use cambered airfoils, maybe with a limited AoA, they can do what they want, those cars will generate a lot less turbulence than currently

F1 uses the second wing, for as much as you can divide them in those three classes. The wings are highly optimized to bring the best downforce in incredible ranges of AoA.

Sorry but you only have to look at any wing to notice the upper side is concave, maybe they´re not perfectly flat, but neither cambered
The endplates show the airfoil perfectly, remember the AoA, the wing is not leveled, so the upper side is very concave, wich means generate tons of downforce, but lots of drag too. The rear one even with DRS open

You'll end up with teams just optimizing the whole package to suit their needs in a similar fashion again.

Sorry but bs, then no rule do anything, let´s let them total freedom...

Wings follow a basic rule, drag and downforce are proportional, if you force them to use an airfoil and/or limited AoA, drag and dirty air will be reduced, it is this simple

For example, allow ground effect and force them to use cambered wings. Same downforce, less turbulence

If only it was that simple.

Not simple, but posible... if they try. Freezing engines and allowing free airfoils, free AoA, etc they will solve nothing about dirty air, that´s sure

It can only be done so much, it's an effect of the drag created by the car. So to reduce turbulence, you'd need less drag. The only way to really force less drag through is to limit power, as then the drag can't be overcome so easily anymore. Which brings the next issue; People don't like F1 with 400bhp engine packages.

If they´re as fast as now thanks to a more efficient aero wich allows to use smaller engines without increasing laptimes, and they watch much more on track battles because it´s easier to chase a car really close, they´ll be very happy, period

[Pingguest]

In my view the FIA should just specify a maximum amount of downforce, allow passively and actively movable aerodynamics and homologate the entire bodywork annually. That would improve safety in many aspects, reduce costs, make overtaking possible and still allow creativity.

[wesley123]

First, as Platinum Zeloat said, the unreliability of ground effect was 40 years back, I´d like to think in 40 years engineering has evolved enough.

To a certain extent, sure. However, the laws of physics don't change. The same dangers are still present.

Obviously, but there´re new technologies to solve those dangers, active suspension is the most significant for this case as it can keep the gap constant easily

I'm not certain that would solve the whole thing. What if a car spins off, for example? You get cars taking off.

I'd guess you are right in that active suspension can help maintain a constant gap. However, that would only apply in ideal circumstances. The curb riding example i gave is one example. Remove that constant gap, and your downforce would be gone for a significant amount as it is reliant on that gap.

Sure, you could say "avoid the curbs", but what if an driver goes a little wide? It would certainly mean a serious off.

Anycase ground effect was just an example, if too dangerous there´re many more banned technologies wich may be allowed to compensate the reduction in downforce with wings that does not produce so much dirty air

I'd agree in that, but sadly enough, every upside has a downside.

F1 uses the second wing, for as much as you can divide them in those three classes. The wings are highly optimized to bring the best downforce in incredible ranges of AoA.

Sorry but you only have to look at any wing to notice the upper side is concave, maybe they´re not perfectly flat, but neither cambered
The endplates show the airfoil perfectly, remember the AoA, the wing is not leveled, so the upper side is very concave, wich means generate tons of downforce, but lots of drag too. The rear one even with DRS open
http://origin.lb.formula1.com/wi/gi/597 ... rn3038.jpg
http://i.kinja-img.com/gawker-media/ima ... x3emyx.jpg

sorry, misinterpreted you there. i thought you meant the literal profile and not the camber. But yes, I agree, those high cambered wings do bring a good amount of turbulence with them.

You'll end up with teams just optimizing the whole package to suit their needs in a similar fashion again.

Sorry but bs, then no rule do anything, let´s let them total freedom...

Wings follow a basic rule, drag and downforce are proportional, if you force them to use an airfoil and/or limited AoA, drag and dirty air will be reduced, it is this simple

True.

It can only be done so much, it's an effect of the drag created by the car. So to reduce turbulence, you'd need less drag. The only way to really force less drag through is to limit power, as then the drag can't be overcome so easily anymore. Which brings the next issue; People don't like F1 with 400bhp engine packages.

If they´re as fast as now thanks to a more efficient aero wich allows to use smaller engines without increasing laptimes, and they watch much more on track battles because it´s easier to chase a car really close, they´ll be very happy, period

I'm not so certain. Cars are definitely able to trail closer after the '09 rule change(and more after '14 one).

There were talks of the PU's being upped to 1000hp because apparently they aren't strong and loud enough. Lowering these numbers will have people complain of how un powerful the cars are and how a GP2 car has more power.

however, this gave me a thought. LMP-1s are capable of pretty large power even thought they have quite the fuel flow limit, because of that, draag is of much more concern. So instead of reducing power, reduce the allowed fuel/fuelconsumption to make drag of a serious consideration.

[Miguel]

There were talks of the PU's being upped to 1000hp because apparently they aren't strong and loud enough. Lowering these numbers will have people complain of how un powerful the cars are and how a GP2 car has more power.

The problem with power is actually being compared to road cars. F1 power figures no longer look ridiculous.

Ten years ago, F1 had ~900 BHP, and the most* powerful exotic you could purchase was an Enzo with ~660 BHP. Now, F1 have ~800 BHP (rough estimate, I admit) but LaFerrari's, P1's and Porsche 918's all make around 900 BHP. Plus the Veyron. Or the Koeniseggs. Even "normal" stuff like a F12 or an Aventador or a Corvette C7 Z01 make around 700 BHP.

There are more pressing issues in F1, but waving HP figures is easy and fixing aero rules is hard. How can you write a rule book without loopholes that still allows F1 cars to have development and be the fastest thing around a track on 4 wheels and still allow overtaking?

[sgth0mas]

I definitely agree with you miguel. F1 cars just arent very impressive anymore when you look at todays cars. Especially since F1 cars have gone backwards and consumer cars forwards. In america we have greately benefited from a resurgence of the horsepower battles between the big 3.

With the reduced quality of racing, and relatively less impressive cars, theres not as much incentive to follow closely.

[J.A.W.]

Given the long-proven ability of high speed aero-features on A2A missiles capable of multi-Mach manoeuvring..
..it seems self-evident that devices akin to those system types could be adapted to F1..

Either as an automatic aero-deployment in the event of a departure from control attitude, for winged use..
..or as a pop-out fail safe in the case of integrated ground effects downforce designs..

I agree - the tightly proscriptive rules are stifling the technical development & the racing spectacle..

[Andres125sx]

Anycase ground effect was just an example, if too dangerous there´re many more banned technologies wich may be allowed to compensate the reduction in downforce with wings that does not produce so much dirty air

I'd agree in that, but sadly enough, every upside has a downside.

Sure, but do you really think FIA and/or Bernie took the best decisions lately?

Their basic route is, "I can´t change aero too much because top teams will complain, so let´s try to solve aero problem with poor tires, devices that give unfair advantages to some cars (DRS), etc."

I can´t agree with this route, now the problem is even bigger, because aero problem is still here, but there are new problems due to this absurd rules. The most frustrating to me is they´ve managed to ruin the most exciting part of racing, overtakes. Some seasons back it was very difficult to overtake, but when somone did, it was amazing because it was a tough battle. Today there´s no battles at all, any overtake is due to DRS, wich does not give oportunity to defend (option 1, aero does not allow you to start the straigh close enogh so you can´t overtake, option 2 you can, and top speed difference is just too high to defend), or because of different tires wich make the car in front some seconds slower, any other case and overtaking is not possible, even with cars more than 1 second quicker

This will continue the same until someone realice aero is the real problem

If they´re as fast as now thanks to a more efficient aero wich allows to use smaller engines without increasing laptimes, and they watch much more on track battles because it´s easier to chase a car really close, they´ll be very happy, period

I'm not so certain. Cars are definitely able to trail closer after the '09 rule change(and more after '14 one).

There were talks of the PU's being upped to 1000hp because apparently they aren't strong and loud enough. Lowering these numbers will have people complain of how un powerful the cars are and how a GP2 car has more power.

however, this gave me a thought. LMP-1s are capable of pretty large power even thought they have quite the fuel flow limit, because of that, draag is of much more concern. So instead of reducing power, reduce the allowed fuel/fuelconsumption to make drag of a serious consideration.

That´s a different approach for the same goal I´m proposing, improve efficiency

As Miguel said, today it´s not possible for F1 to impress due to total power, they´d need 2000bhp, and still there will be production cars with that power soon, so that cannot be the route anymore. Also that would generate innase top speeds, so no the route definitely

IMO FIA should impulse efficiency, that´s what they´re doing right now with new turbo engines, so continue that route. I think if F1 continue with similar laptimes but with smaller engines each season that would be impressive. Brute power does not impress anyone anymore, F1 does need new challenges, like using smaller engines and matching current laptimes.... that´d be something wich would highlight F1 technology and IMO would make F1 impressive again

Forcing teams to use cambered airfoils for the wings wich reduce drag, but allowing active wings would improve efficiency by a good factor, for both wings. To keep similar top speed and laptimes you´d need to reduce total power because drag in the straights will be a very small fraction than currently (while keeping similar downforce on the corners thanks to movable wings) so engines should be really really small

Downsizing is trendy, so apply to F1 too. Imagine F1 with 0.8l engines and full active wings doing same laptimes than today, and also allowing on track battles because aero is a lot more efficient and cars can get closer to each other.... Airfoiled wings will reduce downforce even with active wings, but with engines that small weight will be lower both due to the smaller engine, and a smaller tank as they will use a lot less fuel, so weight could compensate downforce reduction. If i´d be in charge, that´s what I´d do

[Edis]

Also, ground effect aero has been fased out for obvious reasons. It's terribly unstable and just not reliable enough to be deemed safe.

Ground effects was never phased out, the current cars still produce a significant share of the total downforce by underbody ground effects (the front wing also operate in ground effects). The ground effects was however significantly reduced in the early eighties by the requirement of a flat floor. Before that, F1 had been running what was essentially inverted wings in the full length of the sidepods. Since the wings you can fit in the sidepods are very long and narrow they are very sensitive against leakage. This is why low ground clearance is important, and even sliding skirts were used to seal the underside of the car from air leaking in from the sides. While sliding skirts isn't allowed anymore, many racing series continued to use underbody tunnels, although not as extreme as those used by F1 in the early eighties/late seventies. Modern ground effect cars tend to use vortex generators to seal the underbody rather than sliding skirts, and the bottom is often stepped to prevent the cars from bottoming out.

Look at the late Champcars for instance and you will notice that they have underbody tunnels, and not just the short diffuser with a flat floor that you find on F1 cars. The design trend in Champcar before its demise was to increase the share of downforce generated by ground effects. I think that trend have continued in Indycar, at least one of the three concept proposal for a new car produced almost all of it's downforce by the center section of the underbody using ground effects. The purpose was to allow the cars to follow each other more closely - which I think F1 is in need of too.

[mrluke]

Delta wing uses ground effect for its downforce, none of the horror crashes discussed in this thread have occurred to it yet.