why cant you see the airflow?

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adam2007
adam2007
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Joined: 30 Mar 2009, 14:34

why cant you see the airflow?

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why cant you see the air flow over the wings when the car is doing like 160mph? if you get what i mean?
like all the "white" air going over the wing showing the vortex's and etc

wesley123
wesley123
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Joined: 23 Feb 2008, 17:55

Re: why cant you see the airflow?

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because air dont got any colour?

If air got an colour we couldnt see anything
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tomislavp4
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Joined: 16 Jun 2006, 17:07
Location: Sweden & The Republic of Macedonia

Re: why cant you see the airflow?

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Yup, air is invisible man, it doesn't matter if you are moving through it with 5mph or 500mph, it will remain invisible :wink:

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horse
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Joined: 23 Oct 2009, 17:53
Location: Bilbao, ES

Re: why cant you see the airflow?

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adam2007 wrote:why cant you see the air flow over the wings when the car is doing like 160mph? if you get what i mean?
like all the "white" air going over the wing showing the vortex's and etc
The tip vortices are always there, you just do not see them all the time as the humidity and speeds are not high enough. The white stuff is basically clouds forming about the vortex cores and their appearance is governed by a complicated interaction between the temperature/pressure change caused by the vortices and the humidity/dew point of the air.

You can try and follow this wikipedia article Wingtip vortices
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Scotracer
Scotracer
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Joined: 22 Apr 2008, 17:09
Location: Edinburgh, Scotland, UK

Re: why cant you see the airflow?

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The only thing you see is the condensed water in low-pressure areas, such as the wing-tip vortices.
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PNSD
PNSD
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Joined: 03 Apr 2006, 18:10

Re: why cant you see the airflow?

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Though the previous posts are 100% correct, along with the use of flow-vis we do sometimes get these rare moments where we can see airflow ;-)!

Image

Just_a_fan
Just_a_fan
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Joined: 31 Jan 2010, 20:37

Re: why cant you see the airflow?

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adam2007 wrote:why cant you see the air flow over the wings when the car is doing like 160mph? if you get what i mean?
like all the "white" air going over the wing showing the vortex's and etc
Sometimes you can. It just needs the correct atmospheric conditions. We saw it last year in the wet races just before it rained. At least some rear wing tip vortices were visible; don't remember seeing any under wing flow condensing though.
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Giblet
Giblet
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Joined: 19 Mar 2007, 01:47
Location: Canada

Re: why cant you see the airflow?

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I've posted this image before.

Image

It's all just fluid.
Before I do anything I ask myself “Would an idiot do that?” And if the answer is yes, I do not do that thing. - Dwight Schrute

adam2007
adam2007
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Joined: 30 Mar 2009, 14:34

Re: why cant you see the airflow?

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how do they show the air in wind tunnel then? they spray it on the wing you can see it sepeate over the wing? i saw some airflow of rear wing ages ago just strands of air

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raymondu999
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Joined: 04 Feb 2010, 07:31

Re: why cant you see the airflow?

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What they do if I'm not wrong is use some smoke (or something white I'm not sure what it's called lol) in the air in front of the car. That way as the grey airflow (colored by the smoke goes through the car with the air, it's possible to see the airflow.
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kalinka
kalinka
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Joined: 19 Feb 2010, 00:01
Location: Hungary

Re: why cant you see the airflow?

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It is indeed visible in right conditions :

http://www.f1today.nl/fotos/p305lco66.jpg

You can see a few examples on above page.

High hunidity/high speed i think.

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Lurk
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Joined: 13 Feb 2010, 20:58

Re: why cant you see the airflow?

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I remember that at the end of the 90's, vortex were clearly visible on rear wings... (as in kalinka's link)
Giblet wrote:It's all just fluid.
But water density is not the same as air density, so flow is not the same :wink:

Giblet
Giblet
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Joined: 19 Mar 2007, 01:47
Location: Canada

Re: why cant you see the airflow?

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Don't worry, my tongue must not have been entirely in me cheek there.

In that pic, the car was going very slowly, so the visual effect at that speed might have been similar looking to what the air would like like at very high speed.
Before I do anything I ask myself “Would an idiot do that?” And if the answer is yes, I do not do that thing. - Dwight Schrute

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Lurk
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Joined: 13 Feb 2010, 20:58

Re: why cant you see the airflow?

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Well... My native langage is not english so I'm not sure of the signification of your first sentence...

No problem with your second one :wink:

ps: is canadian flag for hockey final? Anyway it was a great match!

Giblet
Giblet
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Joined: 19 Mar 2007, 01:47
Location: Canada

Re: why cant you see the airflow?

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Sorry Lurk, I just mean that I was being sarcastic about the fluid. I thought the question was odd that someone was surprised they couldn't see air.

Oh yes, the flag is for the hockey final, but also just in bragging recognition about our new Olympic record, and how well the Olympics went.

The luge accident not withstanding, but that was for the most part unpredictable, although very sad.
Before I do anything I ask myself “Would an idiot do that?” And if the answer is yes, I do not do that thing. - Dwight Schrute