testimento
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Burster charge for FAE, ignition risk?
I was wondering that what explosives are used to disperse the fuel-air bomb flammable liquid without igniting it? I have understood that explosions
easily cause very high point blank temperatures aside of the reaction, which could potentially ignite the liquid. Is this true?
On the other hand, if the explosive, let's say PETN or ETN, was used to disperse a not-so-flammable liquid, for ex. chemical agent, into aerosol,
could this be carried out with ordinary construction methods or could the liquid ignite? If it was rated like lamp petrol, diesel fuel, etc. The
liquid should be so dispersed that the median range would be at least few meters.
To return the subject, when the aerosol is in the air, what methods are used to ignite the blast cloud within measured time? I understood the timings
are between 10 to 50 milliseconds. If the initiating blast doesn't set the liquid off, why shall the detonator do so? Does it have to do with the
fuel-air mixture so that the UEL is much more over the range upon primary detonation, but when the fuel is mixed with the air, a small gap is enough
to set it off at detonation velocity?
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Ral123
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You are not a military corporation to be able to make FAE weapon. All you can do is a charge with thermobaric effect by adding aluminium to certain
materials.
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Melmoth
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The risk of igniting the initially formed cloud in present systems would be nihil. A bursting charge of 1 to 2% of the fuel weight is used. The mass
of the burster charge to fuel ratio has little effect on resultant cloud dimensions once the ratio exceeds 1:40. The purpose of this burster is to
break open the fuel container and distribute the fuel in a cloud with sufficient
volume to contain enough oxygen for complete initiation.
Present FAE systems are fitted with a two stage fuze, the delay time between dispersion and initiation is of the order of 150 ms
Traditional systems include fuels like Ethylene Oxide, Ethylene Oxide, Kerosene or Aluminium Powder.
More recently developed 'single stage' munitions consist of a chemical initiation, a hypergolic approach uses bromine trifluoride or choline
trifluoride that are able to
react with the fuel. Perfluorohydrazine is the interacting two component initiator.
Adding Al, Although enhancing blast characteristics for a lot of explosives, is not automatically considered thermobaric..
"This species has amused itself to death"
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franklyn
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Igniting how ? Placing the dispersing charge in the center of the fuel container , precludes ignition. A proper FAE first creates the aerosol cloud
which is detonated by the air shock wave of a second explosion. The second explosive charge is propelled away by the burst of the fuel container to
explode an instant later at a short distance. Timing is crucial to proper function. Designing the delay is key. No flame except for a brief flash is
evident. If there is flame , only then it is properly called ' ignition ' because no detonation has ocurred.
Related post
http://www.sciencemadness.org/talk/viewthread.php?tid=8741#p...
The distinctions between High Explosive , Fuel Air Explosion , and Thermobaric enhanced blast High Explosive._
http://www.youtube.com/embed/IkeOHh8AoBM
American FAE BLU-96/B
Super Russian FAE
http://www.reuters.com/resources/flash/embedvideo.swf?editio...
Thermobaric is explosive enhanced for blast _
http://www.youtube.com/embed/tCcH8pmXShw
* note Aluminum also sensitizes the Nitromethane.
The air shock wave of a very large ton sized FAE kills inside of armored vehicles where the occupants are protected from fragment producing
explosions. Thermobarics are most effective inside enclosed areas such as building's or tunnels. Outdoors , the un-degraded high explosive , producing
fragments as those from grenades are more effective. Cluster bombs take this to the ultimate conclusion.
http://www.youtube.com/embed/9wRQSOxse64
Related threads
http://www.sciencemadness.org/talk/viewthread.php?tid=7769
http://www.sciencemadness.org/talk/viewthread.php?tid=7762
http://www.sciencemadness.org/talk/viewthread.php?tid=21691
Further resources _
http://www.sciencemadness.org/talk/viewthread.php?tid=21691#...
.
[Edited on 25-10-2013 by franklyn]
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Melmoth
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Although both are volumetric weapons. Don't confuse an FAE with a Thermobaric explosive.
Fuel - air explosion is presently a two stage event process. dispersion of fuel in air resulting in the formation of a fuel - air cloud, followed by
its detonation. (The current emphasis is to make it a single event process with the elimination of second event. In a single event process, fuel and
an initiating chemical (catalyst) are dispersed simultaneously to form a vapour cloud. The catalyst reacting with either fuel or oxygen in air
produces free radicals to initiate the explosive mixture.
Thermobaric compositions are fuel rich high explosives that are enhanced through aerobic combustion in the third detonation event. In a thermobaric
weapon, the fuel consists of a monopropellant and energetic particles. The monopropellant detonates in a manner similar to TNT while the particles
burn rapidly in the surrounding air later in time, resulting an intense fireball and high blast overpressure.
"This species has amused itself to death"
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franklyn
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Further resources
http://www.sciencemadness.org/talk/viewthread.php?tid=21691#...
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Fantasma4500
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it CAN be done without being militant, keep in mind every single person in this world is just a person..
http://www.youtube.com/watch?v=7dW1qkBg8sM
i wouldnt be able to do it, probably just because im a fucking potato at electronics and such delay stuff, lol
but as you might understand what is needed is a good fuel, hexane or butane fx.
if you take some real HE and a few lighters and strap to it (with common sense, not facing them towards anything including you that shouldnt not get
hit by fragments) it should form a decent fireball in which most of it depending on spread of the fuel should combust in very little time, but might
look slow due to excess fuel that will keep on burning after the fuel cloud is gone already
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