The bigger the group the better. Release a hundred or more balloons all tied together with by their strings that you light before you release them, they burn and separate and as the strings reach the hydrogen they blow up.
A spectacular air explosion display for very little money, very easy to do with readily purchased materials.
Inspired by Flying Toaster's pointing out that flying balloon ghosts should use hydrogen instead of helium because they can explode. Co-invented by both of us I guess.-- doctorremulac3, Oct 19 2014 (?) Hydrogen balloons a-'splodin' https://www.youtube...watch?v=nLuOM9aOWvk [doctorremulac3, Oct 20 2014] Once more with feeling https://www.youtube...watch?v=ce6imsXTkGQhydrogen+oxygen balloons. A squeaky pop perhaps? (note these are smaller balloons than in the doc's link above.) [Loris, Oct 20 2014] Spark rifle Spark_20rifleFor use with oxyacetylene Lawrence Welk bubble machine. [bungston, Oct 21 2014] cheap AND dangerous [+]-- ixnaum, Oct 20 2014 Heh heh! Yeaa.-- doctorremulac3, Oct 20 2014 Easier just to throw one of those 15kg Butane gas bottles on a big fire, old housemate told me the local bikers did that once, none of them could hear 3 days afterwards mind you..
Hmmmm....-- not_morrison_rm, Oct 20 2014 It'd be easy to put some magnesium powder into the balloons before inflating too. [+]-- AusCan531, Oct 20 2014 Much, much bigger bang if you use hydrogen+oxygen, or even hydrogen with air.
[+]-- MaxwellBuchanan, Oct 20 2014 This was something I wanted to do when I was about eight.
//Much, much bigger bang if you use hydrogen+oxygen, or even hydrogen with air.//
These have the additional 'advantage' of not having the same lift, so the bang is close enough to really feel the benefit.
(Note: hydrogen+oxygen is significantly bigger bang than hydrogen+air; some caution may be advised.)-- Loris, Oct 20 2014 Caution, smaution. Guy in welding school filled a bread bag with acetylene gas and tossed it onto the flame cutter, the explosion brought down dust from the roof beams 15 metres about, and the wrath of the overseer. How we laughed.
If you want to see total masculine insanity + flammable gases + sledge hammers + grinding wheels + large hydraulic guillotines, I can definitely recommend welding school.-- not_morrison_rm, Oct 20 2014 Told the story before, but my episode of "Greatest Childhood Explosions" featured 1) laying out a big line of gunpowder about ten yards long with a big pile at the end that was supposed to burn like it did in the cartoons, slowly like a fuse, (it doesn't) 2) putting a bunch of primers at the bottom of a jar, powder on top and THIS TIME a fuse of sorts, a layer of flammable glue on top to allow us time to run to a safe(er) distance. 3) and of course the m-80 in the milk carton that turned the carton, and almost my hand, into a beautiful flower looking modern art sculpture.
Ahh, to be young, stupid and reasonably well equipped with explosive materials.-- doctorremulac3, Oct 20 2014 <nostalgic sigh>
//throw one of those 15kg Butane gas bottles on a big fire //
Bad idea. Place the bottle and then build a bonfire round it - that way, there is some (mostly illusory) control of the direction of the flame.
// none of them could hear 3 days afterwards mind you.. //
Depends on the failure mode. Sometimes there's just a jet of flame from the top of the bottle; more rarely, the true BLEVE, which scatters the fire over a huge area and has to be seen to be believed.
Don't rely on sandbags for protection; a ditch or trench is essential. If the tank bursts, lumps of hot metal go whirring in random directions at great speed.
As to the idea, [MB] is correct. Hydrogen will just burn, with relatively little flame; introducing a proportion of oxygen, even if the mixture isn't stoic, will give a much more satisfactory result.-- 8th of 7, Oct 20 2014 I think you get your mixture from the hydrogen under pressure expanding when the balloon pops and mixing with your surrounding oxygen in time to get all the ingredients for explosive goodness.
See link-- doctorremulac3, Oct 20 2014 Ignition propagates from the point at which the balloon is penetrated by the flame. There's turbulence as a jet of hydrogen is emitted, but the mix isn't stoic, so it burns instead of exploding. As the rubber pulls away, the hydrogen continues to burn at the gas/air interface.-- 8th of 7, Oct 20 2014 //but the mix isn't stoic//
That's very difficult to prove. It's almost impossible to determine the state of mind of the hydrogen either before or during the combustion. It may be resigned to its fate, but we're unlikely to know for sure.
However, we can be fairly certain that the mix is not stoichiometric.-- MaxwellBuchanan, Oct 20 2014 I wasn't going to say anything.-- doctorremulac3, Oct 20 2014 Eighth, Eighth... You're forgetting that we coat our balloons in thermite.-- Loris, Oct 20 2014 If you painted a spiral of explosive material on a long sausage shaped balloon and lit it it would ignite in a spiral fashion and form sort of a corkscrew of flame.-- doctorremulac3, Oct 20 2014 At school the students (boys only) would take apart the giant screws from the bomb shelters, put some match heads inside between two screws, and then simply throw it high enough and far enough.
When it falls, it explodes loudly and propels the parts way up. One hit the third floor next to our classroom, and took a big chunk off the wall, next to the class's "good boy" who stayed in the classroom and was watching carefully from the window.
Some years ago, we were at the entrance to a 'youth village', waiting for a group of kids to reach the gate, after a "sea to sea" 3 day cross of Israel through the Carmel mountains. all of a sudden one of the giant flag poles fell to the side. All the large screws were screwed off and missing, presumably for the exact same reason as above. Whoever did it, never thought that the flag poles would actually fall. Luckily no one was hurt.-- pashute, Oct 20 2014 Dammit MB, I was just going say that...
// stoichiometric.
It could be stoichioImperial, we don't know if hydrogen has gotten around to Metric yet...might still be on £.s.d for all I know-- not_morrison_rm, Oct 20 2014 /mental state of hydrogen/
I would think more epicurean than stoic, given its penchant for mixing it up with other atoms.
/bag of acetylene/ I recall mathing this out and judging that acetylene should be buoyant. So disappointing to find video of such a bag, very unbuoyant. I think there may even be video linked somewhere on the HB if the idea still exists.
..found it linked under one of my ideas but no movie at link.-- bungston, Oct 21 2014 random, halfbakery