Dirty air sensitivity and regulations

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hollus
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Re: Dirty air sensitivity and regulations

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turbof1 wrote:Mind however that I feel the wing itself should not produce downforce on its own if you want to combat turbulent wake of a car in front.
Take that idea to the extreme. Ground effect that produced lots of downforce and wings, both wings, that produce lift with a mandatory profile. You can still keep the current overall levels of downforce.
If the wings suffer more than the underfloor when in turbulent air, then you have a following car that gets higher downforce and less drag.
But surely we do not want to take it to that extreme, do we? It makes me think of another sport where following gives you significantly less drag and, in that case, somewhat higher power (by providing references and targets). In that sport the key skill is not to lose contact with the ones in front:
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Rivals, not enemies.

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turbof1
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Re: Dirty air sensitivity and regulations

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That sounds like a reasonable concern. So a bit of front wing downforce then?
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miqi23
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Re: Dirty air sensitivity and regulations

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turbof1 wrote:
rjsa wrote:Well, the wing IS part of the car, so that's what I was reading... never saw the OTHER
Hence the ambiguity. When he stressed on this a couple of times:
What I should have said, and what I've tried to clarify, is that the front wing doesn't add to the car's form drag
It hit me he implied that with 'car' he meant every other part of the car except the front wing. It's the internet missing context phenomenon. We would never have this discussion if this was being talked over in person.

To get this back on course:
Due to the aforementioned interaction with the wheels, which would be exceptionally easy to optimize with spec components, the front wing isn't an especially egregious contributor of induced drag. Because the wing has no impact on frontal area, it doesn't contribute to form drag [of the other parts of the car]. Plus, a standard front wing can be used to greatly minimize the many types of drag associated with exposed, spinning wheels...
I think that is correct in the sense you have wheel arches or an open alternative of it. Concerning turbulent airflow from the wheel this is beneficial. Mind however that I feel the wing itself should not produce downforce on its own if you want to combat turbulent wake of a car in front. So maybe it's best not to call such a device a front wing.

Using ground effect might be a solution regarding having the car generate downforce. I still stand with my opinion that ground effect cars, and in turn fan cars, would generate a massive amount of turbulent airflow, hence why it has to be combined with a big rear wing to upwash the turbulent flow, and a absence of front wing (but again, a device in front solely focussed on countering turbulent wheel wake is recommended!).

You say that you are of the opinion that ground effect cars would generate massive amount of turbulent airflow and a bigger rear wing is required to upwash the turbulent flow, it sounds like you are referring to the ground effect cars of the 80s like this one here Image although the rear wing on that car is not that cambered but since it produces down-force there is an element of upwash to move the tunnel outlet flow upwards.

Do you think these cars did not suffer any down-force loss when following each other?

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turbof1
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Re: Dirty air sensitivity and regulations

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miqi23 wrote:it sounds like you are referring to the ground effect cars of the 80s like this one here
Almost spot on. I'm referring perhaps to the first ground effect car which had centre of pressure issues forcing it to run a giant rear wing.
although the rear wing on that car is not that cambered but since it produces down-force there is an element of upwash to move the tunnel outlet flow upwards.

Do you think these cars did not suffer any down-force loss when following each other?
Well, before going deeper into your question, I have to stress I can be wrong. Yes, I have doubts about my own opinion since although overtaking and close racing back then was much, much better, the performance differences in the several aspects (cornering speed, top speed, acceleration) was highly 'varianced'. How much of the close racing can be attributed to the concept of upwashing the mass flow, and how much to the performance differences?

Also it has to be stressed those cars evolved like that 'naturally': ground effect cars like that have their centre of pressure quite forward, meaning you have to balance it out with a big rear wing. Along with issues of extracting the flow out of the diffuser which were also cured by a big rear wing. The GE car you showed is a little bit more evolved with the centre of pressure more backwards, hence the smaller rear wing.

Further note that even though that car has a low cambered wing, it is fairly close the diffuser which certainly benefits upwash (although more camber would have enhanced the effect for sure).

Will there still be loss of downforce? Yeah probably. Any solution involving downforce will inevitable lead to turbulent wake issues. But the idea is this might be less because you are more dependent on GE interaction and your front downforce is not generated by a front wing which is more sensitive. The idea is also by upwashing the turbulent airflow, the car leaves a low pressure wake behind it to have an inwash of more laminar flow.

Atleast that's my opinion/idea :P.
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Andres125sx
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Re: Dirty air sensitivity and regulations

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turbof1 wrote:Will there still be loss of downforce? Yeah probably. Any solution involving downforce will inevitable lead to turbulent wake issues. But the idea is this might be less because you are more dependent on GE interaction and your front downforce is not generated by a front wing which is more sensitive. The idea is also by upwashing the turbulent airflow, the car leaves a low pressure wake behind it to have an inwash of more laminar flow.

Atleast that's my opinion/idea :P.
That was my idea too, until Bhall conviced me any solution, including GE, will inevitably evolve enough to finally be very sensitive to dirty air. GE on the 80s were great because they were new, but if they´re developed futher they will also be very sensitive to dirty air, and the problem will remain the same

That´s the reason I changed my mind and started thinking about solutions to fight that drop in DF due to sensivity of very developed solutions. If dirty air is inevitable, and sensitvity of F1 aero will always cause a drop in DF, the only way I can think about to solve the problem is adjustable DF levels so even if F1 cars keep sensible to dirty air, adjustable DF can solve or minimize the problem

Then Bhall talked about dity air caused by fans wich would be worse, and I agree. But only if the fan is used directly. If the air exit is channeled to a less sensible area (for example RW endplates so the fan airflow goes over the trailing car), then, even if it still causes some dirty air, it will be less severe than any other solution disturbing air at the same height the trailing car will pass.

I think this way the solution might:

1- Increase DF at will when in dirty air so the problem is reduced
2- Not cause increased wake turbulence at the important height (car height) thanks to the channeled exit at highest car height, and facing up (so the wake turbulence is produced even higher)
3- Even reduce dirty air as a fan wing does not need any highly cambered wing/flap so it might reduce FW drag
4- It can keep same airflow deflectors to reduce tire drag and could even be more efficient as that would be its only purpose, contrary to today when they also try to generate DF

So it might reduce dirty air (reduced drag), be less sensitive to the remaining dirty air (thanks to the fan), and could compensate the remaining sensitivity to dirty air increasing fan speed and DF

rjsa
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Re: Dirty air sensitivity and regulations

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I think a change of the way aero rules are written is in order. Everything but aero got jackbooted by rulemaking. It's about time it's tried. Letting the aero chiefs of the teams deciding by unanimity what can and what can't be changed will get no one nowhere.

Standard GE and all the floor facing geometry, minimum radius for everything, may be even a convex hull rule. Limited elements and restricted geometry on wings. And last but not least 'less letter' of the law and more 'spirit of the law' all the way.

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turbof1
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Re: Dirty air sensitivity and regulations

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rjsa wrote:I think a change of the way aero rules are written is in order. Everything but aero got jackbooted by rulemaking. It's about time it's tried. Letting the aero chiefs of the teams deciding by unanimity what can and what can't be changed will get no one nowhere.

Standard GE and all the floor facing geometry, minimum radius for everything, may be even a convex hull rule. Limited elements and restricted geometry on wings. And last but not least 'less letter' of the law and more 'spirit of the law' all the way.
2 things:

1) You'd be facing complete standarization (which ultimately is as Ben described the truly only option)

2)'spirit of the law' is not an easy concept. You'd basically need to give an entity total power to arbitrarily accept or refuse aero solutions.

I'm not sure if that sacrifice is worth closer racing. It'll definitely be a great help towards getting closer racing, but the series will not be any more interesting then for instance super formula.
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rjsa
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Re: Dirty air sensitivity and regulations

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turbof1 wrote:
rjsa wrote:I think a change of the way aero rules are written is in order. Everything but aero got jackbooted by rulemaking. It's about time it's tried. Letting the aero chiefs of the teams deciding by unanimity what can and what can't be changed will get no one nowhere.

Standard GE and all the floor facing geometry, minimum radius for everything, may be even a convex hull rule. Limited elements and restricted geometry on wings. And last but not least 'less letter' of the law and more 'spirit of the law' all the way.
2 things:

1) You'd be facing complete standarization (which ultimately is as Ben described the truly only option)

2)'spirit of the law' is not an easy concept. You'd basically need to give an entity total power to arbitrarily accept or refuse aero solutions.
1) Is this car racing or or an Aerodynamics engineering challenge? Why is freedom in aero so important?

I say make 80% of it standard and leave 20% to be developed. If it gets complicated just change it again. If you don't have that much reward spending will fall and it will cease to be so important and so expensive.

We're running standard tyres and ECUs for crying out loud.

2) We are seeing how good democracy is turning out. I actually spend more time bitching than watching. And I'm over spending money on it.

rjsa
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Re: Dirty air sensitivity and regulations

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turbof1 wrote:I'm not sure if that sacrifice is worth closer racing. It'll definitely be a great help towards getting closer racing, but the series will not be any more interesting then for instance super formula.
Last but not least: It's not only closer racing. It's fugly cars, long dominances, DRS, being held hostage by silly ruling.

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turbof1
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Re: Dirty air sensitivity and regulations

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1) Is this car racing or or an Aerodynamics engineering challenge? Why is freedom in aero so important?
It's getting pretty philosophical, but that question will vary from person to person, depending on their interests. For me personally, it is both. So aero is important for me as well. Again, that's a personal answer on this.
2) We are seeing how good democracy is turning out. I actually spend more time bitching than watching. And I'm over spending money on it.
I agree the current government structure is disfunctional. I don't believe that is down to democracy, but down to many people involved who respresent company interest. Perhaps the biggest issue for me is the existance of FOM. In football the clubs are directly seated in a committee which negotiates broadcasting rights. It's amazing how quickly you can get everyone's noses pointed in the same direction when they are directly responsible to sell a common product.
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mrluke
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Re: Dirty air sensitivity and regulations

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We still havent established that "removal" of dirty air will actually help get closer racing.

I know its an accepted "fact" but is there any empirical evidence to support it?

As a thought exercise I would suggest that of all the field, the most difficult car to overtake (assuming you can match or better their laptimes) is going to be your team mate because your cars are the same. Its not that the hardest car to overtake is the one that makes the most "dirty" air.

rjsa
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Re: Dirty air sensitivity and regulations

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There is no removing of dirty air IMO, only controlling sensitivity to it.

rjsa
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Re: Dirty air sensitivity and regulations

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turbof1 wrote: I agree the current government structure is disfunctional. I don't believe that is down to democracy, but down to many people involved who respresent company interest. Perhaps the biggest issue for me is the existance of FOM. In football the clubs are directly seated in a committee which negotiates broadcasting rights. It's amazing how quickly you can get everyone's noses pointed in the same direction when they are directly responsible to sell a common product.
I'll beg to differ regarding FOM, I think the teams are the problem. FOM will keep it's mouth shut as long as the cash is flowing.

Using the football analogy fails IMO, because this would be the equivalent of teams maneuvering to decide which team can hire who, how many players in each side the size of the field and goals and so on, every handful of years - and that would not fly either:

http://www.auto-motor-und-sport.de/form ... gn=Formel1

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