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Fighting Fires With Beams of Electricity
cylonlover writes "It's certainly an established fact that electricity can cause fires, but a group of Harvard scientists have presented their research on the use of electricity for fighting fires. In a presentation at the 241st National Meeting & Exposition of the American Chemical Society, Dr. Ludovico Cademartiri told of how they used a unique device to shoot beams of electricity at an open flame over one foot tall. Almost immediately, he said, the flame was extinguished. 'Such a device could be used, for instance, to make a path for firefighters to enter a fire or create an escape path for people to exit, he said. The system shows particular promise for fighting fires in enclosed quarters, such as armored trucks, planes, and submarines.'"
Like streams of electrons or ions?
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
Anyone have any idea how this thing actually works?
The best I could come up with is based on a very small part of the article:
So I guess what happens is that the electrical field charges the soot and other light carbony things generated in the fire, which causes them to disperse sort of like what happens with this toy? How does that help extinguish the fire, though? Wouldn't the outward motion of the carbon particulates just bring in more oxygen?
What other effects are going on?
Water dripping off you, down your neck, sliding around in foam and soaked to the skin kind of wet. You could pee your pants and know one would even know, except for the funny coffee smell, kind of wet. The fist thing that happens is utilities disconnect the gas and power meter before anyone enters the structure (power and water don't mix). Never mind the Scott packs. Now water around your feet and a battery strapped to your back where do you put your Scott pack? Also your gear already weighs about 60 pounds with Scot pack. This is stupid we already have a grenade like device that will snuff out a fully engulfed house for 12 minutes the only side effect is a fine white powder on everything.
Woo! Time to submit my patent to the PTO:
"Description of Selachimorpha-mounted Electrical Fire Suppression Systems"
The road to tyranny has always been paved with claims of necessity.
If there's a story that is crying out for some audio-visual documentation, this had got to be it!
I mean electricity and fire (and maybe they use a laser to create an ionized channel for the electricity to go through).
All they had to do was reverse the polarity!
It's so simple!
Ice Cream has no bones.
Who cares about putting out the fire... I just want the Lightning Cannon.
Evil Overlord Notice #1 : Discontinue Operation : Weaponize Shark immediately.
Evil Overlord Notice #2 : The Commissary of Evil will be serving fish sticks all week.
I hear if you do something like that they give you this cool award named after that evolution dude. Go for it man!
Monstar L
Let's see them take on a metal-fluoride fire! For those, I've always recommended a good pair of running shoes.
Hyperbole: I use it liberally!
This would be a fun way of extinguishing the candles on your birthday cake...
Might even work with those "prankster" candles that relight ... :)
Danilo Odell: Yeah, what the hell was that thing?
Lieutenant Worf: Automated fire system. A force field contains the flame until the remaining oxygen has been consumed.
Danilo Odell: Ah, yeah, w-what if I had been under that thing?
Lieutenant Worf: You would have been standing in the fire.
Danilo Odell: Yeah, well, leaving that aside for the moment, I mean, what would have happened to me?
Lieutenant Worf: You would have suffocated and died.
Danilo Odell: Ye-ah, sweet mercy.
Flames are ionised (i.e. charged) particles. If you have a strong enough electric field (which is really not the same as 'shooting electricity' as per the article) when the charged particles move through the electric field there will be a force on them perpendicular to their motion and to the field i.e. the flame will curve over into spiral.
If you could get this to happen on a large enough scale, the flame would suppress itself as instead of the flame moving away from the fuel it would hang around - stopping oxygen from reaching the fuel.
If this all sounds really unlikely, that's because it is. Here it a video showing an electric field affecting a small candle:
http://www.youtube.com/watch?v=6fKGeV4NrrA&feature=mfu_in_order&list=UL
It looks like you need an electric field on the order of 10keV per 5cm to get this effect. So if you wanted to do it on a fire that was say 5 meters across you'd need an electric field in the order of 1MV which while obtainable is not exactly an easy thing to setup - particularly when there's a fire going on.
"Free software as in beer, copy protection as in racket" - Telsa Gwynne
Sir,
You have electric and magnetic fields confused with each other. If you have a MAGNETIC FIELD, when charged particles move across (NOT along) it, there is a force on them perpendicular to their motion (and to the field, incidentally).
In an electric field, the force on the charged particle depends on the orientation of the electric field, not on the orientation of the charged particle's momentum.
I refer you to the Lorentz equation, which goes like this:
F = q (E + V cross B)
where capital letters denote vector quantities and "cross" is the cross-product operator. As you can see, the force from the electric field (q times E) is parallel to E. The force from the magnetic field (q V cross B) is perpendicular to both the magnetic field and the particle's velocity.
I'm not sure whether the rest of your explanation holds water--when you have a rapidly changing electric field it is accompanied by a magnetic field, which WILL curve particles like you say. In fact, when you have both, you have what is called an "E cross B" drift, in which charged particles have a motion perpendicular to both the E and the B field. (Is that what you meant?)
And yes, IAAP.
--PeterM