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Author: Subject: Considered LE or HE?
rsgpit
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[*] posted on 19-5-2006 at 12:46
Considered LE or HE?


The stoichiometric mix of hydrogen/oxygen reacts at 8160fps. I know ANFO is considered HE and detonates at 4000mps. Hydroxy is about half that speed. Anyone know what it is considered.

Whatever it is though, gallon baloons make a hell of a bang.
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Chris The Great
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[*] posted on 19-5-2006 at 14:00


H2 and O2 can move from burning into detonation if yo have enough. Same with acetylene. Nearly every gas/air mixture will do this but H2/O2 does it exceptionally easily, the same with acetylene. Your balloons are probably big enough for the pure O2/H2 to detonate, H2 and air needs over a 1m diameter before it begins to move into detonation.
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Axt
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[*] posted on 20-5-2006 at 01:32


Attached is extracts of "Explosives" by Brunswig (1909), shows the importance of initiator strength of the VOD of hydrogen-oxygen mixtures using in 5mm tubes. Its actual flame propogation through small openings is only 38m/s as determined by Bunsen (of "bunsen burner" fame). Detonated with mercury fulminate or strong electric spark 2H2/O2 reaches ~2706m/s. I'm sure these are diametre dependant but theres some hard figures for you.

That and.. I really have a pet hate towards vague or non descriptive thread titles :mad:

[Edited on 20-5-2006 by Axt]

Attachment: velocity-of-hydrogen-oxygen.pdf (855kB)
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Boomer
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[*] posted on 21-5-2006 at 08:05


Also, for you it is interesting whether it makes DDT on its own. I doubt it detonates in 5mm pipes without a blasting cap or a strong electric pulse to kick-start it.
You might therefore have a look at:

Attachment: detonations in pipes and in the open.pdf (89kB)
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rsgpit
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[*] posted on 21-5-2006 at 12:39


But what about the larger balloons, would they detonate? Ive made up to 1yard diameter balloons with electrolysis, and they shake the bushes 30 feet away. There are not dust clouds from moving earth though like in other HE's. It also is not a reaction that liberates gases. It makes water obviously, but it is the high temperature steam that the heat makes that expands and creates the shockwave. If it does detonate in larger volumes just from a fuse, It would be the easiest HE to make. Electricity+water.
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Swany
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[*] posted on 21-5-2006 at 19:15


I have a friend who electrolysed enough 3% H2O2 to make a garbage bag full, taped a fuse to it, and ignited while watching from a fairly close distance, I belive he said 5m. Well, when the fuse ignited the mixture. He was thrown on his ass, deafened, and very surprised, as he expected a fireball, not a sharp boom with no light.

My interest is piqued. :P
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12AX7
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[*] posted on 22-5-2006 at 04:23


Seems to me electrolysis of H2O would leave a lean mixture, i.e. H2 diffused out of the bag. But then, H2O2 would be even more lean if anything.

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nitro-genes
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[*] posted on 22-5-2006 at 06:21


Why use H2O2 for electrolysis of water? A few % sulferic acid, and all alkaline earth metal cations in combination with phosphates, nitrates, carbonates and hydroxy anions (the soluble ones) produce oxygen at the anode and hydrogen at the cathode in a 1:2 molar ratio...
If you add a little dishwash detergent to your electrolysis cell, the gas will be trapped in soapy bubbles on the surface which you can light with a match. This will give an idea about its power. The smaller bubbles make an earringing bang, a very large one will shatter a glass cell...
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12AX7
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[*] posted on 22-5-2006 at 06:24


Heh, this one time I found bubbles on top of a chlorate cell being ran at a rather high voltage. (The bubbles were forming partly due to the graphite scum floating about.)

Needless to say I won't attempt lighting such bubbles again :P :D

Tim




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enhzflep
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[*] posted on 22-5-2006 at 07:16


I knew one particular individual, who is usually very particular, and would never light a match toward himself for fear of the danger (for lack of a better analogy)

This one particular time, so he tells me, he decided to investigate just how explosive acetylene was. Okay thinks I, nothing too surprising to be found out here. Until, he mentioned something about soap, water and a bathtub!:o

Yup, that's right he decided to test the stuff INDOORS, in the bathroom. LOL.
having mixed oxy and acetylene in water bombs (5cm diam - & one at a time), 1.25L soda bottles and 4L ice-cream buckets as kids on a mate's farm, I could only imagine where this was leading...

Turns out he had "a fair few" - I didn't ask, bubbles filled with said mixture on top of the water when he threw the match in. :D :D :D

Cost him something like a hundred bucks to replace the window + another 5 years for the jokes about bubble-baths to stop. Not bad, for somebody who's employed as an industrial chemist.


However, to get back on to topic - is anybody familiar with the dynamics of liquid hydrogen/oxygen rockets? Am wondering if the reaction proceeds at the full 2706m/s. I.e is it a continuous detonation as it were, or 'mere' burning?
I read with interest that the two are mixed through mazes of very small holes, before being sent into the combustion chamber. I gather that it is to effect greater mixing, with what I can only presume would be correspondingly high reaction rates.
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