turbulence??

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JiMbO
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Joined: 25 Mar 2008, 04:50
Location: Stockholm, Sweden

turbulence??

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we all know how sensitive f1 cars are when following another car so do you think teams design certain aerodynamic devices to disrupt the airflow as much as possible behind their car

i often hear martin brundle talk about the "dirty air" when one car is following another. he says thats why is so hard for a car to follow less than 7/10ths behind one it's trying to overtake

so if a team could disrupt the "diry air" so much so that a car would not be able to follow less than a second behind it would give them a compeditive advantage and make it very diffcult to overtake said team..??

bazanaius
bazanaius
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Joined: 08 Feb 2008, 17:16

Re: turbulence??

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Possibly. I think the disadvantages (namely increased drag) would probably outweigh the advantages though. I think the problem with following lies mostly in the sensitivity of the car to turbulence, and so a greater focus probably goes into improving that rather than hindering others.
If you do this you'll have a higher L/D ratio and so be quicker. Disrupting your trailing airflow won't help you overtake other people, it will only prevent them overtaking you. I'd rather be in front and able to pull away due to my better L/D than not being able to overtake and having to ensure I dont make any mistakes as the guy behind is only a second away.

my $0.02, others?

Jersey Tom
Jersey Tom
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Joined: 29 May 2006, 20:49
Location: Huntersville, NC

Re: turbulence??

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Nastier the airflow behind your car the more drag you'll have. The goal is to make your car go fast, not to make someone behind you go slow.

As it stands, with F1 cars being so aero sensitive, you could pull a decent draft behind someone but heaps of your front or rear downforce will vanish. According to Bourdais, the front vs rear thing even depends on what type of car you're following and their aero setup.

Plus, the whole turbulence thing would work ok for denying someone behind you good corner entry or mid-corner grip maybe.. but down a straightaway they could (a) draft off you and then (b) get out of your wake and blow right by given the amount of drag your car has.

Nascar even has this problem, of aero sensitivity.
Grip is a four letter word. All opinions are my own and not those of current or previous employers.

coreybaxter
coreybaxter
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Joined: 02 Oct 2007, 05:32
Location: USA

Re: turbulence??

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I know this doesnt deal with turbulence but the heat or "hot air" coming off of a car is another reason cars can't be to close behind another. Not sure if that would have an affect .7 sec back??

Ogami musashi
Ogami musashi
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Joined: 13 Jun 2007, 22:57

Re: turbulence??

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The problem of turbulence in racing car and especially with F1 is very complex and can't be addressed by simple rules.

The major thing to understand is that turbulence is due to three major contradictory effects: Induced vortices, Slipstream and diffuser wash.

Those three combine to created a vastly low pressure turbulent area.

The problem is that those three tend to originate from opposite proprieties, Slipstream originate from drag, Induced vortices from downforce and diffuser upwash from diffuser angle.

If you do not do carefully when taking one measure, you actually worsen the others.

That's why there's no simple solution to that but i must say next year ones will really have a good effect i think.

roost89
roost89
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Joined: 10 Apr 2008, 19:34
Location: Highlands, Scotland

Re: turbulence??

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Image
wouldn't the diffuser wash lift the nose of an f1 car off the ground? the reason I'm asking is because in the picture above the diffsuer appears to be lifting alot of airand I'd assume it would do the same to the car following.
"It could be done manually. It would take quite a while, but it could be done. There is however a much more efficient and accurate way of getting the data. Men with lasers." Wing Commander Andy Green

Ogami musashi
Ogami musashi
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Joined: 13 Jun 2007, 22:57

Re: turbulence??

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Until the front wing aft section stalls (diminishing the effective camber) the upwash can't really account for a negative lift coeficient, i mean the upwash decreases the effective AOA of the wing but the camber of the wing means that the Cl is high so it would require quite steep upwash to induce lift.

However the vortices coming from the wing can sometimes downwash and in this case the angle of attack increases above the Clmax stalling the wing.