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N2O - should I buy it ?

Posted: Sat Aug 20, 2011 6:19 am
by POLAND_SPUD
so I found some really cheap N2O cartridges... Do you think I should buy them ??
http://allegro.pl/naboje-do-bitej-smiet ... 56620.html

how useful would they be ? my understanding is that N2O needs elevated temperature to decompose into oxygen... so I couldn't use it instead of air, right ?

I would need a typical air/fuel mix to start the reaction, but that means that my mix would be totally off once it decomposes

uhmm I guess some help would be useful

Posted: Sat Aug 20, 2011 6:26 am
by jackssmirkingrevenge
Considering all N<sub>2</sub>O does is provide extra oxygen to the combustion, it doesn't seem to make sense to add it to a metered pressurised mix - there are much easier ways of achieving the same effect.

Posted: Sat Aug 20, 2011 6:34 am
by POLAND_SPUD
easier ways? what easier ways? an oxygen tank requires a special reg and stuff

lol I could still use it for recreational use :D jk
Nitrous oxide is said to deflagrate somewhere around 600° Fahrenheit (315°Celsius). It can also easily be ignited using a combination of the two. At 600 psi for example, the required ignition energy is only 6 J, whereas N2O at 130 psi would not react even with a 2500 J ignition energy input
hmm

Posted: Sat Aug 20, 2011 6:54 am
by jackssmirkingrevenge
POLAND_SPUD wrote:easier ways? what easier ways? an oxygen tank requires a special reg and stuff
Er... increase the mix number?

If you have a say 15mL of butane in a 100mL chamber at 4 bar, that's a 5x mix. Adding Nitrous oxide to the mix isn't going to help, because you already have all the oxygen you need in the compressed air.

Say you wanted to add more fuel, say 3mL more - simply pressurise to 1 bar more, simples ;)
lol I could still use it for recreational use :D jk
It would make a great pick-up line :D Excuse me miss, does this capsule smell of nitrous oxide to you?

Posted: Sat Aug 20, 2011 7:06 am
by POLAND_SPUD
It would make a great pick-up line
I guess that Diethyl ether would be better for that application - but you already know that
Er... increase the mix number?
I was hoping there is some magic way that I don't know of... and yeah I do realize it isn't going to help if I add it

though this seems interesting
Nitrous oxide is said to deflagrate somewhere around 600° Fahrenheit (315°Celsius). It can also easily be ignited using a combination of the two. At 600 psi for example, the required ignition energy is only 6 J, whereas N2O at 130 psi would not react even with a 2500 J ignition energy input
my understanding is that it wouldn't require mixing at all... though I am not quite sure how to ignite it (but it seems that at high enough pressures it could be ignited with a spark ignitor) or how powerful would it be

I guess DYI could shed some light on it... if he responds

Posted: Sat Aug 20, 2011 7:15 am
by jackssmirkingrevenge
Are you suggesting a high mix at atmospheric pressure with nitrous oxide thrown in?

I guess you could try a smaller combustion chamber that then ignites a main N<sub>2</sub>O and fuel chamber... seems more trouble than it's worth though.

Posted: Sat Aug 20, 2011 7:24 am
by inonickname
Could do a chamber of high pressure N2O with a burst disk and spark gap for a HV arc to decompose all the N2O which bursts the disk. A small amount of liquid fuel could be added behind the projectile

Posted: Sat Aug 20, 2011 7:25 am
by POLAND_SPUD
nope right now I am suggesting using it as a monopropelant... at least that's my understanding of the article on it in wikipedia

I skipped an important part from that quotation, that would have been clearer
Nitrous oxide can also be used as a monopropellant, for example for use in rockets. For this, the nitrous oxide needs to be brought to a high enough temperature or a high enough pressure.
Nitrous oxide is said to deflagrate somewhere around 600° Fahrenheit (315°Celsius). It can also easily be ignited using a combination of the two. At 600 psi for example, the required ignition energy is only 6 J, whereas N2O at 130 psi would not react even with a 2500 J ignition energy input

Posted: Sat Aug 20, 2011 7:26 am
by inonickname
As I just suggested :roll: but why not use it as a monopropellant and add a liquid fuel behind the projectile (eg. ethanol or methanol) for additional gas and temperature

Posted: Sat Aug 20, 2011 7:31 am
by POLAND_SPUD
yeah that's what I meant
it seems it would be even more interesting for you jsr as it should be able to provide even MOAR power than a typical hybrid (well at least that's my understanding) and that can be used to reduce the size of the cartridges

edit
Check the references section on wikipedia. I am not sure if it would be safe to fill cartridges with N2O and liquid fuel at the same time (though that would simplify things a lot). Care would have to be taken to reduce adiabatic heating as that could potentially cause decomposition

Posted: Sat Aug 20, 2011 8:13 am
by jackssmirkingrevenge
POLAND_SPUD wrote:yeah that's what I meant
it seems it would be even more interesting for you jsr as it should be able to provide even MOAR power than a typical hybrid (well at least that's my understanding) and that can be used to reduce the size of the cartridges
Point taken but it would be easier for me to just obtain an oxygen cylinder though...

Posted: Sat Aug 20, 2011 8:24 am
by inonickname
POLAND_SPUD wrote:yeah that's what I meant
it seems it would be even more interesting for you jsr as it should be able to provide even MOAR power than a typical hybrid (well at least that's my understanding) and that can be used to reduce the size of the cartridges

edit
Check the references section on wikipedia. I am not sure if it would be safe to fill cartridges with N2O and liquid fuel at the same time (though that would simplify things a lot). Care would have to be taken to reduce adiabatic heating as that could potentially cause decomposition
You don't need to. N2O in a chamber with burst disk, igniter. Liquid fuel (alcohol) in between projectile and burst disk. Electric arc decomposes N2O which bursts the disk, and ignites the fuel with the now present oxygen, and propels the projectile. Like the dieseling ideas people throw around.

Posted: Sat Aug 20, 2011 9:16 am
by POLAND_SPUD
You don't need to
yeah, I know but the question is - can it be done safely?

get a cartridge, add a few drops of ethanol, fill with N2O to ~700 psi.. and voila - you hazzz a simple yet powerful cartridge... no mixing needed just a powerful enough ignition system


...though I realize it wouldn't be that difficult to add another burst disk to the design... maybe I shouldn't try to make things as simple as possible
Point taken but it would be easier for me to just obtain an oxygen cylinder though
this thing wouldn't need mixing - that's the point

just add a few drops of liquid fuel, top off with N2O and that's it

Posted: Sat Aug 20, 2011 10:21 am
by jackssmirkingrevenge
Hmmm... a 700 psi pre ignition pressure is pretty high though, don't you think?
Equivalent to over 50x... the cartridge is going to need a pretty good burst disk holder.

Posted: Sat Aug 20, 2011 10:24 am
by Technician1002
Enhanced oxygen combustion by it's very nature is dangerous. This is not for random experimentation. Study it first. Build with proper materials. Safety first. Beware some NOS cartridges has other stuff in them to discourage recreational use as when abused can cause permanent injury or death. It is not a toy.