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Author Topic: How does fire get extinguished in the presence of wind?  (Read 1597 times)

Offline boner

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The above one is the question i want to ask u all.....


 

Offline CliffordK

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How does fire get extinguished in the presence of wind?
« Reply #1 on: 12/01/2011 20:45:56 »
Fire essentially requires 3 things.

Air (oxygen)
Fuel
Activation Energy.

Without any one of the elements, you have nothing.

So, if you light a match....  then wave it in the wind, you get too much cooling, and thus inadequate activation energy to maintain the reaction.

Once started, however, wind can provide formidable challenges by providing the fire with lots of air (oxidizer) and blowing the flames around.

You still might be able to make some progress with the basic principles.  Prevent the oxygen from reaching the fuel...  by either removing the fuel, or covering it with something like water (which will also cool the fire).

A variety of mechanisms are used when fighting forest fires.  Terrain can be helpful.  Fires like to burn up hills, and slow down with burning down, so ridgelines would become natural fire breaks.  One can also burn up some of the fuel ahead of the fire with small controlled burns.
 

Offline Soul Surfer

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How does fire get extinguished in the presence of wind?
« Reply #2 on: 12/01/2011 23:31:36 »
A lot of what we recognise as fire is flames.  these are inflammable gasses produced by the heading up of unburnt material by the hot core of the fire which is usually a burning solid like carbon.  Dependant on the gases involved and the proportion and mixing of air these have a particular combustion velocity and if air flow (wind) is faster than this combustion velocity this flame can be blown away from the core of the fire that keeps it alight and will be extinguished  ie blown out like a candle.  on the other hand adding more air (a strong draft) to a glowing carbon fire will increase its heat like blacksmith's bellows.
 

Offline Airthumbs

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How does fire get extinguished in the presence of wind?
« Reply #3 on: 13/01/2011 00:04:31 »
I think you will find that in the presence of CH4, this would exacerbate the problem rather then extinguish it!  ;D
 

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How does fire get extinguished in the presence of wind?
« Reply #3 on: 13/01/2011 00:04:31 »

 

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