Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
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jimmy101
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Sun Mar 29, 2009 2:30 pm
D_Hall wrote:CpTn_lAw wrote:What if you were to find a flammable liquid that contains its own oxidizer?
Then you're most likely playing with hydrazine. Would it work? Yes.
But let me put it this way... From time to time "play" with hydrazine at work. We wear "moon suits" when we do so and it *still* scares the crap out of me.
I think the "
would it work? yes" is a bit misleading and/or optimistic.
Could you get it to work in a plastic pipe system with parts you picked up at the local hardware store? Probably not. At least not more than once, and not without taking pretty significant risks to life and limb.
There are other monopropellants that could be used, high conc. H2O2 springs to mind. All are about as dangerous as hydrazine.
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Biopyro
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Sun Mar 29, 2009 3:50 pm
Yes, you gain power in that comparison, but why not just have the potato all the way down or fuel it with propane.
It really isn't worth the effort when you could get the same gain by doing something much simpler.
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety. -Benjamin Franklin
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D_Hall
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Sun Mar 29, 2009 5:12 pm
jimmy101 wrote:Could you get it to work in a plastic pipe system with parts you picked up at the local hardware store? Probably not. At least not more than once, and not without taking pretty significant risks to life and limb.
True, but since he opened the monopropellant door he's already in effect stated that he's not dealing with systems that can be had via the local hardware store.
There are other monopropellants that could be used, high conc. H2O2 springs to mind. All are about as dangerous as hydrazine.
Again true, but I don't think it quite fits the definitions the poster was asking for. He was asking about a combustion system. Peroxide (as a monopropellant) doesn't burn; it simply decomposes. If that's all we're after, a better system would probably be nitrous oxide. At least it's readily available.
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D_Hall
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Sun Mar 29, 2009 5:14 pm
chrissilvermancs wrote:yes well that's the resion i posted it because i wasn't sure that it is posible but tell me this though, why dose it give jet engines more thrust, when they can as u say just increase the size.
Because jet engines don't normally burn all the oxygen that's available to them. The same can not be said of gun systems.
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jimmy101
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Mon Mar 30, 2009 9:56 am
D_Hall wrote:jimmy101 wrote:Could you get it to work in a plastic pipe system with parts you picked up at the local hardware store? Probably not. At least not more than once, and not without taking pretty significant risks to life and limb.
True, but since he opened the monopropellant door he's already in effect stated that he's not dealing with systems that can be had via the local hardware store.
There are other monopropellants that could be used, high conc. H2O2 springs to mind. All are about as dangerous as hydrazine.
Again true, but I don't think it quite fits the definitions the poster was asking for. He was asking about a combustion system. Peroxide (as a monopropellant) doesn't burn; it simply decomposes. If that's all we're after, a better system would probably be nitrous oxide. At least it's readily available.
Yes, but isn't hydrazine a monofuel? Or, at least, hydrazine can be used as a monofuel so it to dosn't "burn" in the normal sense. Not really any different than high conc. H2O2. With both you have a pretty significant toxicity worry (hence the "moon suits") as well as the worry of something unexpectedly catalyzing the fuel's decomposition.
Heck, even acetylene can be used as a monofuel, though I woudn't recomend it.
