Ground Effect - Bring It Back

[Andres125sx]

@ Andres

landing flap setting is chosen to give a greater Cd and a so lower lift/drag ratio - because you want to descend
because of this lower L/D ratio you will be unable to climb with landing flap (more or less)
so takeoff flap is chosen to give a greater L/D ratio

That´s what I said, isn´t it?

For landing you use a configuration with more drag because you´re descending but also want to decrease speed, so in this case drag is good, higher drag means lower L/D ratio, while to climb you don´t want too much drag, what means higher L/D ratio

WT comes from pressure difference above and below wing - ie lift coefficient regardless of how this is achieved
the main difference between landing flap and takeoff flap is the Cd - not the lift coefficient

Full flap deployment does not increase lift ratio?

Drag increases more than lift what decreases L/D ratio, but lift also increases, or I´m wrong?

btw
leading edge flap is also used with little or no trailing edge flap (ie first and last stages of flap use)

What about the picture I posted above? It shows both leading and trailing edge flaps deployed

[bhall II]

Yes it looks like that, the thread goes about GE, and you keep ignoring that arguing about wings

Are you sure about that? (Please don't just skim through it this time.)

All cars have more or less the same front wings, barge boards, floors, diffusers, rear wings, etc.



What sets the cars apart from one another is how well those components are integrated into a larger system, and it's all in the details. In other words, the best front wing isn't necessarily the one that creates the most downforce; it's the one that most seamlessly and consistently works with the rest of the car.

The problem with "dirty air" is far less about its effect on any single component in isolation; it's the deleterious effect on the interaction of those components within the system that's the real problem, and it's one that cannot be solved by simply replacing one component with another.

You will not make the car less sensitive to "dirty air" by replacing a flat floor with a pair of venturi tunnels. You will only make the floor (marginally) less sensitive to "dirty air." (And I believe it's highly doubtful the safety brigade will ever allow underbody downforce to be a car's primary source of downforce, because it's way too sensitive to ride height changes.)

This is where "dirty air" and performance differentiation converge. A trailing car will always tend to have worse aerodynamic efficiency than a car in "clean air." So, a trailing car will always tend to need a non-aerodynamic advantage in order to overtake, which the current formula doesn't allow. Hence, DRS and/or futility...

Put another way, and specifically with regard to overtaking, if every car has an aerodynamic device, it's as if none of them have it, as overtaking is about performance differentiation. They cancel each other out, because physics and rules that make all the cars more or less the same size dictate that the respective profiles of all aerodynamic devices across all teams will always tend to be the same.

[Moose]

Put another way, and specifically with regard to overtaking, if every car has an aerodynamic device, it's as if none of them have it, as overtaking is about performance differentiation.

That's clearly not true.

Every car has wings, yet your statement that every car gains the full advantage of them is not true. A car following another one in dirty air does not get the full advantage of their wings.

The entire point of this thread is to find an alternative aerodynamic system where your statement is true, or at least closer to true than the current system.

[bhall II]

Don't leave out the last part, because it's important.

Put another way, and specifically with regard to overtaking, if every car has an aerodynamic device, it's as if none of them have it, as overtaking is about performance differentiation. They cancel each other out, because physics and rules that make all the cars more or less the same size dictate that the respective profiles of all aerodynamic devices across all teams will always tend to be the same.

The profile and orientation of an aerodynamic device is dictated by the airspeeds in which it will predominantly be used. The size of F1 aerodynamic devices is limited by rules that restrict the size of the cars. Combined, that means all aerodynamic devices will tend to be the same in F1. When it comes to overtaking, a process that inherently requires difference, that means it's all effectively irrelevant, and that will hold true for nearly every possible aerodynamic solution you can imagine.

Back when overtaking was more commonplace, it was driven by rules that allowed for different engines and different tires.

Though I believe the impact would be short-lived due to the tendency for competitive strategies to converge upon the optimum, fan cars might work, since it's the only device that's 100% immune to the effects of "dirty air." But, I also think it would likely just shift the focus of "dirty air" sensitivity to other parts of the car, because underbody downforce has always been the least sensitive to disruption anyway.

I can't think of a just way to implement proper active aero, because I can't think of a way to help out the third car in a line of cars. Being allowed to temporarily activate more downforce if you're trailing another car is all well and good. But, what about the driver behind that car who suddenly finds himself in extremely "dirty air"?

Every solution seems to have these kinds of drawbacks, and this is why I think that, as paradoxical as it may seem, the search for an aerodynamic solution to "dirty air" is probably a futile one.

[zeph]

Wow, a lot of thoughtful posts here. I don't think about aero on the level of some people here, but I'm not gonna let my ignorance get in the way of my opinion.

Or you know, stick a fan on it.
The concept of "dirty air" will cease to exist because the fan will simply have to do less of a job if there´s a car in front moving air out of the way for it.

I don’t think it will magically cease to exist, as long as objects move through air at high speeds there is always going to be turbulence, but I think I agree with you in principle.

What a fan car like the Brabham BT46B could accomplish, in my mind, is that the upper body could be optimized for aerodynamic efficiency (low drag) as the fan is supposed to take care of the downforce.
So the wake will be different, but not non-existent.

I always thought it was a real shame that the fan was disallowed. It seemed like a much better solution than the Lotus 79’s venturis.

Which got me thinking about rain, what effects did the brabham have on a wet track?

They only raced it once, GP of Sweden in 1978, dry conditions, and won by a comfortable margin. They were forbidden after that and never raced again.

Though I believe the impact would be short-lived due to the tendency for competitive strategies to converge upon the optimum, fan cars might work, since it's the only device that's 100% immune to the effects of "dirty air." But, I also think it would likely just shift the focus of "dirty air" sensitivity to other parts of the car, because underbody downforce has always been the least sensitive to disruption anyway.

I’m not well-versed in the intricacies of aerodynamics, but like I said above, I would think if a fan took care of downforce, it would allow the upper body to be optimized for minimum drag?

There would still be ‘dirty air’, that will never go away, but presumably of a different nature, and I imagine it would not have as much effect on the following car’s aerodynamic grip.


edit:
Actually, now that I think about it, most of the dirty air would obviously be coming from the fan...

But if the fan would indeed reduce (or negate entirely) the need for upper-body downforce and thus allow for a low-drag design, the dirty air would likely have much less of an impact. Both because low-drag designs would presumably reduce turbulence behind the car, and be less sensitive to or dependent on airflow anyway.

Sounds like double whammy to me, or am I missing something?

[bhall II]

Sounds like double whammy to me, or am I missing something?

A fan car would still need a strong front wing for quick turn-in, and that tends to be the first aspect of performance affected by "dirty air."

What made the BT46B so devastating is that it was the only fan car in the field, and the lore surrounding it has been enhanced by an extremely brief service time. Had the concept been allowed to develop, I think its shortcomings would have become more clear. It's without question a novel tool, but I don't think it's the end-all, be-all of performance.

The idea can't be completely glazed-over, though, because it's thus far the only device impervious to "dirty air," and it's one that can create virtually limitless amounts of downforce without creating a huge upwash in its wake.

[FW17]

[Andres125sx]

Yes it looks like that, the thread goes about GE, and you keep ignoring that arguing about wings

Are you sure about that? (Please don't just skim through it this time.)

Could say the same....

Dirty air does not affect perfomance differentiations, but makes it more or less relevant. With a lot of dirty air you need huge perfomance differences to overtake because the trailing car need to keep a gap before the straight, so to overtake the perfomance difference need to be huge

But if there´s little dirty air, or less, then the trailing car can start the straight much closer to the car in front, so perfomance difference need to be much smaller to overtake.

Little dirty air and overtaking will be posible with small perfomance differences. A lot of dity air, and overtaking will be posible only with huge perfomance differentiations.


So if you keep same pefomance differentiations beteween cars, but minimize dirty air problem, overtaking will be easier

So if you keep same pefomance differentiations beteween cars, but minimize dirty air problem, overtaking will be easier

And what I've said is that it's next to impossible to minimize the "dirty air" problem in a developmental racing series that moves toward greater aerodynamic sensitivity as a matter of course and, incidentally, devotes an entire track session toward making sure that the faster cars start a race ahead of the slower cars.

But then....

The idea can't be completely glazed-over, though, because it's thus far the only device impervious to "dirty air," and it's one that can create virtually limitless amounts of downforce without creating a huge upwash in its wake.

So finally it looks like the thread is not totally useless, and dirty air problem could be minimized, contrary to what you had been asserting repeteadly till now

[zeph]

Sounds like double whammy to me, or am I missing something?

A fan car would still need a strong front wing for quick turn-in, and that tends to be the first aspect of performance affected by "dirty air."

Are you sure? I know 35 years is an eternity in F1, but I believe both the Williams FW07B and Brabham BT49C (WDC in 1980 and 1981 respectively) lacked front wings because the ground effect rendered them unnecessary. Even the Ferrari 126C2 (the car that would have been 1982 WDC if its drivers had made it to the end of the season) didn't have a front wing.

1982 Was the year I first started following F1 as a wee lad, and I remember most of the cars not having front wings. Googling images is a wash, there are pics of the same cars both with and without front wings. No clue why.

What made the BT46B so devastating is that it was the only fan car in the field, and the lore surrounding it has been enhanced by an extremely brief service time.

Actually, it was devastating in part because both Lotuses had trouble.

But the writing was on the wall, and it would have undoubtedly given the Lotus 79 strong competition.

[zeph]

Images of cars mentioned in previous post, just because it's old-school awesome:

[Tommy Cookers]

WT comes from pressure difference above and below wing - ie lift coefficient regardless of how this is achieved
the main difference between landing flap and takeoff flap is the Cd - not the lift coefficient

Full flap deployment does not increase lift ratio?

Drag increases more than lift what decreases L/D ratio, but lift also increases, or I´m wrong?

btw
leading edge flap is also used with little or no trailing edge flap (ie first and last stages of flap use)

What about the picture I posted above? It shows both leading and trailing edge flaps deployed

full flap setting is designed to give essentially more drag but not significantly more lift than the next-to-full flap setting
because you need lots of drag to be able to adjust the approach angle of descent
eg at London Heathrow a few years ago a BA Airbus had all engines stop on the approach due to fuel icing
the captain reduced flap from full to what I call here next-to-full
the drag was reduced without the lift reducing, and all 350? lives were saved
(if the lift had reduced with the flap reduction a crash was certain)

eg about 40000 Cessna 150/152/172 etc planes had full flap set to 40 deg
the drag typically prevented any climb (ie when abandoning an approach), the pilot having to make an immediate flap reduction
(then around 1982 Cessna cut the full flap setting to 30 deg, and most light planes have this simpler arrangement)

in airliners the LE flap is always deployed with TE flap deployment - these at relatively low speeds
but the LE is also deployed without any (or any significant) TE flap deployment - this at higher speeds eg 200 kt


so I think that WT (tip vortices) of our car depends on the DF more than the drag
the 'extra' drag goes more towards giving the wake a forward velocity ? - this is also a disadvantage (as hollus posted)

[bhall II]

So finally it looks like the thread is not totally useless, and dirty air problem could be minimized, contrary to what you had been asserting repeteadly till now

I initially made the grave mistake of assuming that everyone understands the need to come up with solutions that not only reduce the impact of "dirty air," but are also mindful of the impotence of any changes that ultimately constitute a zero-sum game. Minimizing the effects of "dirty air" is an expensive waste of time if it doesn't lead to more overtaking, wouldn't you agree?

Now, if you want a series in which "dirty air" is totally irrelevant, solving the problem is generally quite simple, and you even get to make a few choices: you can either open up the rules such that genuine aerodynamic performance differentiation is possible or you can standardize virtually everything such that it allows the sport to implement very basic aerodynamic devices that aren't especially sensitive to "dirty air," devices that would otherwise lead to ENORMOUS amounts of downforce (and "filthy air") if given enough room to develop them.

Due to the tendency for development to trend toward the optimum, the effects of the former probably wouldn't last very long, and the latter is actually pre-2015 IndyCar, which is pretty slow by F1 standards.

On the other hand, if you think overtaking should be dictated by power train development, you really don't have to change much of anything in the aero formula; the status quo is more than adequate. (But, it would probably be helpful to relax PU restrictions so that overtaking during the first race won't serve as a near-definitive guide to the vast majority of all overtaking thereafter.)

Absent those wishes, you're pretty much SOL.

I'm not trying to be a dickhead here. It's just that we can't alter reality simply because we want an incongruent result. It's one of the things I love about F1: subjective opinions don't matter, as they tend to be only as accurate as the proverbial broken clock that's nonetheless correct twice a day.

1982 Was the year I first started following F1 as a wee lad, and I remember most of the cars not having front wings. Googling images is a wash, there are pics of the same cars both with and without front wings. No clue why.

I think it's because they were pioneers who were making it all up as they went along. Plus, they had different engines, which allows for performance differentiation in areas unrelated to aero.

(Great pics, by the way.)

[rjsa]

It seems you are assuming your opinion is reality. It is not, it's just an opinion like everyone else's, including mine.

And in my opinion, better freeze aero now and let engines run loose.

[bdr529]

Even the Ferrari 126C2 (the car that would have been 1982 WDC if its drivers had made it to the end of the season) didn't have a front wing.

1982 Was the year I first started following F1 as a wee lad, and I remember most of the cars not having front wings. Googling images is a wash, there are pics of the same cars both with and without front wings. No clue why.

I would think it was up to the driver if he needed or wanted the front wing, as you can see here at the 82 Imola GP
Villeneuve's car without the wing

[Pingguest]

So finally it looks like the thread is not totally useless, and dirty air problem could be minimized, contrary to what you had been asserting repeteadly till now

I initially made the grave mistake of assuming that everyone understands the need to come up with solutions that not only reduce the impact of "dirty air," but are also mindful of the impotence of any changes that ultimately constitute a zero-sum game. Minimizing the effects of "dirty air" is an expensive waste of time if it doesn't lead to more overtaking, wouldn't you agree?

Now, if you want a series in which "dirty air" is totally irrelevant, solving the problem is generally quite simple, and you even get to make a few choices: you can either open up the rules such that genuine aerodynamic performance differentiation is possible or you can standardize virtually everything such that it allows the sport to implement very basic aerodynamic devices that aren't especially sensitive to "dirty air," devices that would otherwise lead to ENORMOUS amounts of downforce (and "filthy air") if given enough room to develop them.

Due to the tendency for development to trend toward the optimum, the effects of the former probably wouldn't last very long, and the latter is actually pre-2015 IndyCar, which is pretty slow by F1 standards.

On the other hand, if you think overtaking should be dictated by power train development, you really don't have to change much of anything in the aero formula; the status quo is more than adequate. (But, it would probably be helpful to relax PU restrictions so that overtaking during the first race won't serve as a near-definitive guide to the vast majority of all overtaking thereafter.)

Absent those wishes, you're pretty much SOL.

I'm not trying to be a dickhead here. It's just that we can't alter reality simply because we want an incongruent result. It's one of the things I love about F1: subjective opinions don't matter, as they tend to be only as accurate as the proverbial broken clock that's nonetheless correct twice a day.

bhall II, you quite rightly argue that overtaking is about performance differentials. With cars performing more or less the same, overtaking is almost impossible; the car's length is effectively increased. Only in case of a driver error or something unexpected a pass can be made. But that very same thing happens with the so-called dirty car. Hence, this issue needs to be addressed. Compare Formula One to Formula Ford and Formula Vee: whereas in Formula One lap times of a following car deteriorates in the wake of another car, the opposite happens in the latter, despite being spec series.