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Author Topic: is the wind chill factor a warming factor?  (Read 2755 times)

Offline CZARCAR

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is the wind chill factor a warming factor?
« on: 24/03/2015 01:14:27 »
I was thinking that an environment of a certain temperature with added wind for a chill factor would actually contain more energy?then that same temperature environment without the wind?


 

Offline Colin2B

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Re: is the wind chill factor a warming factor?
« Reply #1 on: 24/03/2015 08:00:04 »
I was thinking that an environment of a certain temperature with added wind for a chill factor would actually contain more energy?then that same temperature environment without the wind?

In terms of the total environment I think you are right.
Our sensation of temperature depends on the cooling effect on the skin and so both wind and humidity play a part. That's why it's possible to feel cold on a warm day if there is a wind.
 

Offline evan_au

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Re: is the wind chill factor a warming factor?
« Reply #2 on: 24/03/2015 09:46:54 »
A wind turbine can certainly extract more energy out of moving cold air than out of still air at the same temperature.

Unfortunately, moving cold air extracts more energy out of a human than still air at the same temperature.
Human hair and clothes form an insulating layer close to the skin, which reduces heat loss in still air.
Wind blows this insulating layer away, resulting in more heat loss, and a greater chance of hypothermia at the same temperature.

This cooling effect exceeds any heating effect due to the compression of air (at least, for wind velocities in which you could stand up, like < 100km/h).
 

Offline Colin2B

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Re: is the wind chill factor a warming factor?
« Reply #3 on: 24/03/2015 22:57:01 »
A wind turbine can certainly extract more energy out of moving cold air than out of still air at the same temperature.

Is that because of the greater density?
 

Offline yor_on

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Re: is the wind chill factor a warming factor?
« Reply #4 on: 01/04/2015 20:48:29 »
Nope, to the idea Colin :)
A wind should be friction, stealing 'heat' from you, unless that 'wind' comes from a flame thrower in which case one soon will light up the whole neighborhood. It's still a pretty good idea to ask about, as it is about molecules colliding', elevation not involved.
=

the answer seem to lie in the overall direction of molecules. If they have a same direction or not, hitting my skin. But that one should be able to be questioned as a flame thrower can be described as giving the molecules a direction too. Anyway, with a same direction it is assumed that molecules won't lose energy to your skin, instead gaining energy from it.
=

to make it work you will need to assume that a 'overall' motion of molecules will make them lose energy, to then gain relative your mass, aka 'your skins still molecules' as it seems to me. And as it builds on random motions of molecules being forced into one 'direction' by pressure?

Actually I think you could make a argument of pressure stealing energy of the molecules? 'Jiggling' is a measure of energy, and with a pressure inhibiting that 'jiggling' they must lose 'energy'.  But your body consist of matter, not a gas, and so your molecules will have a better resistance to that pressure, and so more energy, than the 'gas' moving against you. A temperature is 'jiggling' and 'colliding', releasing IR.
« Last Edit: 01/04/2015 21:21:23 by yor_on »
 

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Re: is the wind chill factor a warming factor?
« Reply #4 on: 01/04/2015 20:48:29 »

 

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