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Author: Subject: Simplest demonstration of thermobaric principle?
killswitch
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[*] posted on 8-3-2012 at 10:45
Simplest demonstration of thermobaric principle?


Obviously, the purchase and safe handling of ethylene oxide (a near-universal fuel in thermobaric weapons) is beyond the means of most hobbyist chemists. What are some of the cheapest and simplest ways to demonstrate the thermobaric principle (not just FAE, but an actual thermobaric event)?

A tentative scheme I was contemplating was the addition of powdered pyrotechnic aluminium to a fuel-rich explosive composition in a strong container, then wrapping the container with a dead-pressed, oxygen-deficient aluminium flash powder. Is this workable, or is there a better method?

P.S. What exactly do they mean by 'fluorinated' aluminium? Do they mean aluminium trifluoride? Or something like AlH2F?

[Edited on 8-3-2012 by killswitch]
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Ral123
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[*] posted on 8-3-2012 at 12:55


How about NM/Al? May be diethyl ether also. I'm sure there will be termobaric effect from AP-ether-Al in a bucket :D For me unreacted hydrogen is a reliable way to get the effect.
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simply RED
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[*] posted on 9-3-2012 at 01:05


Fluorinated aluminium means aluminium powder covered with teflon/viton etc. Or a multilayer structure of aluminium foil and teflon foil like the structure of an electric capacitor.
See the hundreds of patents floating in the internet.

[Edited on 9-3-2012 by simply RED]




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[*] posted on 9-3-2012 at 08:49


Not really sure if this is "thermobaric", but it is a fun demo that is easy to make with just a few pyro ingredients. Have a small flash powder bursting charge (<.5g confined in a small paper tube. NOT METAL or hard plastic) fused , or with an e-match in it, surrounded by a larger sphere of loosely packed, coarse screened black powder. If using fuse, do so that the flash charge will ignite but the fuse wont start the BP. Hang by a string, or launch as an aerial shell.

In my experiences, the flash throws the powder outward much faster than it can burn. The result is often a bang, followed by a large fireball growing from the middle. You may be able to replace the black powder with fine CuO thermite, or even magnesium dust. Be safe, and don't attempt to make aerial bursting shells without reading up on there safe design, unless you are already experienced.




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KemiRockarFett
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[*] posted on 10-3-2012 at 15:49


Divide Thermobaric explosives from Fuel Air Explosives.

A thermobaric explosive with 30-50 % PETN and the rest Al is a nice working device. Use at least a kg and get it going with a strong initation.

How to demonstrate it? Highspeed camera and pressure measuement as function of time and distance and compare with an ordinary charge as reference or several. Or more indirect by vitnes materials at different distances.

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killswitch
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[*] posted on 13-3-2012 at 07:45


Quote: Originally posted by simply RED  
Fluorinated aluminium means aluminium powder covered with teflon/viton etc. Or a multilayer structure of aluminium foil and teflon foil like the structure of an electric capacitor.


Teflon isn't exactly the best fuel. Is the purpose to transfer the fluorine to the elemental aluminium while the carbon decomposes to CO2? Or is it just a binder to enable longer storage of finer meshes of aluminium?
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simply RED
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[*] posted on 13-3-2012 at 08:08


Teflon is just an oxidizer, quite good by the way... The carbon """decomposes""" to soot...
The purpose of teflon is to react with part of the aluminum, increasing the temperature of the unreacted aluminum enough that it burns in the air when fast dispersed by the main charge of the hellfire missile. That is why not a stechiometrical quantity of teflon is added but 2,3 times less.

[Edited on 13-3-2012 by simply RED]




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