Self Contained Hydrogen Repeater

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.
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 260 times
Contact:

Sat Dec 08, 2018 7:40 am

Can't find the papers for the moment, but from memory, laminar flame front speeds of propane in air at 1 bar ~ 0.4m/s, hydrogen in air ~100m/s, they're both much faster (between 4 and 10 times faster) in stoichiometric mixes with O2 and at pressure.
Good point to reinforce the weapon if you are going to burn hho.This youtuber has an experiment on this.
I already uploaded this video somewhere here, I leave the link:
keks2033
Private 4
Private 4
Russia
Posts: 94
Joined: Mon Feb 08, 2016 2:37 am
Has thanked: 1 time
Been thanked: 5 times

Sun Dec 09, 2018 2:17 pm

I also did the hydrogen gun. The sound of the shot is very sharp and strong, but the bullet flies slowly. Perhaps this is because the tank is small.
[youtube][/youtube]
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 260 times
Contact:

Sun Dec 09, 2018 9:00 pm

I also did the hydrogen gun. The sound of the shot is very sharp and strong, but the bullet flies slowly. Perhaps this is because the tank is small.
At what pressure does the hho compress the combustion chamber? Or shoot at atmospheric pressure? I ask because I can not understand anything in the video. In the future I will try to learn the Russian language, apart from English, (and my own better one). :shock:
It would be good to see the physical properties of this gas, density, for example. Is it denser than air?
keks2033
Private 4
Private 4
Russia
Posts: 94
Joined: Mon Feb 08, 2016 2:37 am
Has thanked: 1 time
Been thanked: 5 times

Mon Dec 10, 2018 12:08 pm

At what pressure does the hho compress the combustion chamber? Or shoot at atmospheric pressure? I ask because I can not understand anything in the video. In the future I will try to learn the Russian language, apart from English, (and my own better one). :shock:
It would be good to see the physical properties of this gas, density, for example. Is it denser than air?[/quote]
hydrogen burned at atmospheric pressure,I was afraid to squeeze it.
[youtube][/youtube]
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 319 times

Donating Members

Tue Dec 11, 2018 6:24 am

keks2033 wrote:I was afraid to squeeze it.
You sound like my first girlfriend :D

*ahem*

This pdf report is worth a read, it's an investigation of the use of hydrogen/oxygen combustion gun as naval artillery by Utron Kinetics, the results were impressive:
UTRON first developed a 15mm gun which successfully proved the concept. UTRON then designed and built a 45mm CLGG gun which successfully proved the scalability of the concept. UTRON’s 45mm CLGG gun project has fired with projectile speeds of 2.5 km/sec. An automatic loader has been developed, installed, and successfully operated. A special fuel-loading system and ignition device have also been successfully developed and deployed. Unique light-gas propellant mixture can be manufactured on the battlefield. The barrel for UTRON’s 155mm gun was designed and manufactured for UTRON by a US Army-owned arsenal. When deployed, the gun, with a muzzle energy of 64 megajoules, will be the most powerful 155mm gun in the world.
Image
UTRON developed and built the 155mm gun that was successfully fired at UTRON’s gun range in West Virginia. UTRON’s CLGG gun has set records for muzzle energy and project velocity for a 155mm gun. The CLGG has experimentally demonstrated velocities great than 4 km/sec (13,120 ft/sec). In some tests, it has demonstrated a muzzle energy increase of 400% when compared to guns with conventional powder propellants.
Image

Oh and look, preloaded hybrid cartridges :D

Image
hectmarr wrote:You have to make many weapons, because this field is long and short life
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 260 times
Contact:

Tue Dec 11, 2018 7:40 am

Very interesting. It's a matter of trying, simply, to compress and see what happens ... :shock:
4 Kpsi son 4 psi x 1000? :roll:
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 319 times

Donating Members

Tue Dec 11, 2018 8:38 am

4 Kpsi son 4 psi x 1000?
Oui monsieur! If you're going to 4000 meters per second at the muzzle, you'd expect a little pre-compression ;)
hectmarr wrote:You have to make many weapons, because this field is long and short life
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 260 times
Contact:

Wed Dec 12, 2018 8:40 am

It is approximately 270 X, impressive and far from the possibilities.
  The interesting thing for adapting this fuel -oxidizer to small things, with much lower compression sizes and pressures, is not needing a propane or butane proportioner to perform the stoichiometric mixture with air. In small gun, it is a real problem to measure with precision, because the hoses, interior spaces of the components, (valves, etc), interfere.
The "problem" is transferred to the hho generator, which should be small, compact, efficient and safe. At first glance, it seems easier to handle, I really do not know. :roll:
User avatar
Cthulhu
Specialist
Specialist
Posts: 194
Joined: Wed Apr 12, 2017 7:07 pm
Location: South Texas
Been thanked: 1 time

Wed Dec 12, 2018 9:44 am

Wow Jack, I had no idea the military actually considered the use of gas guns! I wonder if one day someone on this forum will have their design inspire a new military asset :lol:
hectmarr wrote:It is approximately 270 X, impressive and far from the possibilities.
The "problem" is transferred to the hho generator, which should be small, compact, efficient and safe. At first glance, it seems easier to handle, I really do not know. :roll:
Small generators can still pack a punch!
[youtube][/youtube]
However, I believe if you were to make many guns that work off of stoichiometric oxy-hydrogen, it might be more efficient to use one large precalculated (and therefore more energy efficient) generator and simple connect and disconnect it to your guns as you please.
This weapon serves to silence the noisy speakers of the stupid of the other street! (joke) -Hectmarr
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 260 times
Contact:

Wed Dec 12, 2018 11:04 am

This seems simpler, just to try, because with these designs I do not think they last long. You have to build something more solid and durable, and it should be a dry cell.
[youtube][/youtube]
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 319 times

Donating Members

Thu Dec 13, 2018 5:29 am

Cthulhu wrote:Wow Jack, I had no idea the military actually considered the use of gas guns! I wonder if one day someone on this forum will have their design inspire a new military asset :lol:
In spite of the promising performance it seems that the US Navy is more inclined towards rail guns. They have better performance potential, and do not require pressurized reservoirs of dangerous gasses that can potentially destroy a ship in the event of an accident or battle damage. I can see pressurized cartridges being considered for tank guns though, current weapons max out at around 6,000 feet per second so the performance advantage might justify having more complex ammunition.
hectmarr wrote:You have to make many weapons, because this field is long and short life
User avatar
mark.f
Sergeant Major 4
Sergeant Major 4
Eritrea
Posts: 3627
Joined: Sat May 06, 2006 11:18 am
Location: The Big Steezy
Has thanked: 52 times
Been thanked: 53 times
Contact:

Donating Members

Tue Jan 29, 2019 2:13 am

I'm not one to usually kick up dead topics, but I've been gone a while. :D

The most useful thing, I think, from Utron's work was the inclusion of buffer gases (the simplest being extra hydrogen). In their case, it was to keep their prototypes from eating themselves from the inside.

In the spudding case, the inclusion of buffer gases, which could be as simple as a venturi pickup after the cell for air (nitrogen), would allow something like the original video (with its questionable "soldered together with a total of one correctly sized socket" construction) to be used a little more safely. :wink:
User avatar
Cthulhu
Specialist
Specialist
Posts: 194
Joined: Wed Apr 12, 2017 7:07 pm
Location: South Texas
Been thanked: 1 time

Wed Jan 30, 2019 1:17 am

mark.f wrote:I'm not one to usually kick up dead topics, but I've been gone a while. :D
Don't worry, I was planning on kicking up this thread once I'm finished with this semester. I didn't make the golfball bazooka (http://www.spudfiles.com/combustion-can ... ml#p386065) just for butane :wink:

I've got plans for an attachable self contained HHO generator to mess around with.
This weapon serves to silence the noisy speakers of the stupid of the other street! (joke) -Hectmarr
User avatar
StevenRS11
Private
Private
Posts: 8
Joined: Mon Feb 05, 2018 11:04 pm

Sat Aug 24, 2019 8:00 am

Why not pressurize the chamber using the electrolysis cell itself as the pressure source? I imagine it would actually be a very thermodynamically efficient compressor. Heck, you could probably make the electrolysis cell the chamber itself.
User avatar
Cthulhu
Specialist
Specialist
Posts: 194
Joined: Wed Apr 12, 2017 7:07 pm
Location: South Texas
Been thanked: 1 time

Sun Aug 25, 2019 2:47 pm

StevenRS11 wrote:Why not pressurize the chamber using the electrolysis cell itself as the pressure source? I imagine it would actually be a very thermodynamically efficient compressor. Heck, you could probably make the electrolysis cell the chamber itself.
I was thinking the exact same thing, but sources online keep talking about the danger of compressing hydrogen and I'm not sure auto-detonation is a real danger here.
Either way, I built a cute little HHO core yesterday and I'll be testing it out soon, I'll post my results on trying to get it to pressurize it's own gas.
IMG_20190825_143925.jpg
It has only one positive and one negative electrode on either side with 3 neutral plates in between (this is because I am attempting to run it off of 9 volts). The plates are made of zinc just as a test until I can find stainless steel, I know they will rapidly corrode.
This weapon serves to silence the noisy speakers of the stupid of the other street! (joke) -Hectmarr
Post Reply