I Comparing Water and Ice Melting for fighting fires

Vanadium 50

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This whole thread is based on the idea that water stops fire primarily by cooling it. Except for very small fires (mass of item burning << mass of water), this is not the case. Water works primarily by smothering. Ice pellets with gaps between them will be less effective at smothering than liquid.
 

PeterO

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Hi

Yes, it was my idea also. But that latent heat was the first thing that make me think about it. I didn't do, however, any test. In the same scenario, imagine a ground "band" of 5 meters by 50 m in front of the coming fire just wet by water (what fireman usually try to do so the fire won't spread), and the same belt covered by ice. Wouldn't the second be more efficient in delaying the fire?...

Regards
Any advantage of using ice vs water may be negated by the ability to transport the ice, rather than water, to the deployment location, and then distributing it once you get it there.
As one other responder said, easy to cover a tree/structure with water - very difficult to cover it with ice.
 
Greetings,
Don't know about using ice to fight fires but I had a idea some time ago(Ii do have them sometimes) that a possible way of fire fighting is to use dirt, Thinking mainly of bush fires and places where water is scarce.
My idea was to use some kind of machinery to project a large quantity of dirt or soil etc onto the fire to smother it. Maybe a high speed mobile conveyor and a system to feed dirt/soil onto it. Material could be scooped up locally in the bush by dozers etc. The conveyor should be able to project the dirt a fair distance, be easily moved across the flame front. I guess it would only be useable from bush tracks or trails and in suitable terrain.
 

berkeman

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Greetings,
Don't know about using ice to fight fires but I had a idea some time ago(Ii do have them sometimes) that a possible way of fire fighting is to use dirt, Thinking mainly of bush fires and places where water is scarce.
My idea was to use some kind of machinery to project a large quantity of dirt or soil etc onto the fire to smother it. Maybe a high speed mobile conveyor and a system to feed dirt/soil onto it. Material could be scooped up locally in the bush by dozers etc. The conveyor should be able to project the dirt a fair distance, be easily moved across the flame front. I guess it would only be useable from bush tracks or trails and in suitable terrain.
Dirt is used on small scales to fight wildfires, but any large-scale use of dirt would require the digging/projecting apparatus to be way too close to the flame front on the ground. And given the speed of advance of many wildfires, that's a very dangerous place to be! That's why so much of the firefighting is done with planes and helicopters... :smile:

EDIT: Hey -- check this out. I did a quick search, and there are some situations where your idea is being used!

https://wildfiretoday.com/2011/07/04/dirt-throwing-machine/

upload_2019-3-21_12-33-48.png
 

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LURCH

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Air drops seem to be the most effective tool when fighting wildfires. The tragic example mentioned by the OP sounds like it was partly caused by the grounding of air support. Perhaps the greatest contributions could be made by expanding aerial capabilities.

If the air drops were being performed by very large drones, the restrictions could be relaxed a bit regarding the conditions under which they are allowed to fly. Improved sensors on board, together with better networking of information from all sources, would make the flying much safer, and the delivery more accurate.

NOw that I think of it, people are probably working on both of those ideas already. I am going to search around a little and see if I can come back with some information.
 

LURCH

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Ok, that didn’t take long.
NBC News:
https://www.nbcnews.com/mach/amp/ncna820966
CNET:
https://www.cnet.com/google-amp/news/californias-fires-face-a-new-high-tech-foe-drones/
Fortune:
http://amp.timeinc.net/fortune/2018/11/29/drones-wildfires-california-drones
And this one from Fox News is exactly what I was thinking:
https://www.google.com/search?client=safari&hl=en-us&ei=uWGUXIjwKNX8jwS-l6DgCQ&q=wildfires+aerial+drones+fox+news&oq=wildfires+aerial+drones+fox+news&gs_l=mobile-gws-wiz-serp.3..33i299.1513941.1518269..1518775...0.0..0.355.984.8j3-1......0....1.........0i71j33i22i29i30j33i160.8Qq9_JwL3Kc

A lot more results. Many agencies are working on this, with some of them putting real fire-fighting drones in the air within the year (drones for surveillance of fires are already in use).

Problem with this, of course, is that it will be some time before this tech is widely available.
 
They "stole" my idea about the dirt thrower! I knew I shoulda patented it!
 

256bits

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A lot more results. Many agencies are working on this, with some of them putting real fire-fighting drones in the air within the year (drones for surveillance of fires are already in use).
The lack of drones isn't the problem - it can crash the same as a pilot controlled plane.
The air currents close to and above the fire are the problem.

Keeping an aircraft airborne - someone has to make a decisions regarding safety and effectiveness of deploying water bombers ( as well as ground crew ).
The water bomber has to be able to get low so that the drop of water does not dissipate before reaching the target. For an aggressive fire, that is difficult to do.
The fire in question was so aggressive that it was unsafe for people as well as machinery to be close to the fire front either on the ground or in the air.
The decision to ground the aircraft was done for safety reasons, as well as that the water drops from a height that would be flyable would imprint on dousing of the fire. - the water would evaporate before hitting the ground.
See post 19 for a review of the fire in question.
We are not talking 100's of feet, but thousands, even tens of thousands for safe flying. for an aggressive fire.
 

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