Sciencemadness Discussion Board

HHO combustion questions

NHZ - 25-2-2013 at 14:46

Hi folks, I am an amateur machinist looking to do a project. I want to design a small engine and need to figure out if the following is possible. I would like to generate between 20,000 ~ 50,000 psi contained in a combustion chamber behind a piston. The driving force I would like to use is
HHO gas.

Firstly I would like to know if it is possible to achieve these pressures, my minimum target is 20,000psi in a chamber the size of a large R/C car engine.

I have also heard of an affect when dumping high voltage and strong current into a drop of water fo a different effect called exploding water. Any help on the above topics would be greatly appreciated. This project is still just an idea floating in my head and need to learn some facts before considering going further.


Thanks again.

elementcollector1 - 25-2-2013 at 14:55

Either troll or just plain uninformed.
How the HELL are you going to get 200,000 psi with HHO (which you might want to look up as "H2O"...)?
Also, anyone who says HHO on this board needs to take Chemistry 101 again. Seriously, I'm sick of all of this.

In short,
1) Your process won't work, because that's a ridiculously high pressure.
2) You need to figure out what "HHO" is, and why it won't work.
3) For that 'exploding water', look up "electrolysis of water", figure out its products, and then figure out what they just might do under pressure and with a spark, flame, or even just heat.

NHZ - 25-2-2013 at 15:47

Ahh trolling no.. and if you read my post, its 20,000 / 20K not a 200,000 PSI lol.


When I say HHO, I am simply looking at the natural mix of gases. I apologize you are so offended by this???




I am looking to find some base numbers to work with as I have no experience with this stuff. More importantly I am looking to do things safely.

Again, my question is if a PSI of 20K is possible when Browns gas is ignited in a small enclosure of a few
cu inches, driving a piston forward . The rest of the mechanics to this I will work on from there.

A gasoline engine as inefficient as it is can generate up to 1,000PSI in a cylinder, nitro dragsters even higher. Neither of which
burn a gas, nor mix with pure O2. Im seeing the potential for my idea, but have no idea beyond that.

I am simply researching a concept in my head. I know what I have read, and what has be done, I am looking to change up the dynamics
specifically for my design, and looking for good honest feedback based what experienced people may add to it.


Again, thanks for any and all input...

*EDIT

HHO:
-goal 20,000 ~ 50,000 PSI for a fraction of a second
-if not possible, how many PSI is possible in theory?
-how much difference if any would compressing the mixed gas vs 0psi and only volume


Exploding water:

- have read that it will expand 1800x when instantly converted or atomized with HV and high current, true?
-would a drop of distilled water inside a chamber exposed to the electrodes deliver enough energy to obtain the above goal PSI?







[Edited on 26-2-2013 by NHZ]

watson.fawkes - 25-2-2013 at 17:52

Quote: Originally posted by NHZ  
When I say HHO, I am simply looking at the natural mix of gases. I apologize you are so offended by this???
Because atomic H almost immediately reacts to form molecular hydrogen 2 H --> H2. The oxygen does likewise. The mythical HHO gas mixture only lasts milliseconds and ambient pressure and temperature. The atomic species have already recombined in the gas bubbles off the electrodes.

If you don't know why this matters, look up ΔG for the reactions. (That's the Gibbs free energy.)

bbartlog - 25-2-2013 at 18:48

The difficulty will probably be with actually containing such pressures behind the piston. It is certainly possible to manufacture a cylinder that will resist 20Kpsi pressure; gun barrels and chambers are designed for those kinds of pressures or even higher ones. However, steel tends to start stretching at such pressures... rigid seals that are manufactured to close tolerances (like piston rings) likely won't work because of such expansion, while elastic seals that could handle the expansion won't have anywhere near the strength required to not be blown out. There is a reason that commercial hydraulic equipment tops out at 10Kpsi.

NHZ - 25-2-2013 at 19:02

Thank you for the insight..

Weight is not an issue though my test scale will be small to simplify construction..

I did a quick google as guns were mentioned and found a .22cal chamber pressure is on the order of 20k PSI.
Considering the amount of powder, thats a pretty big number produced in a small area.

Machining tight tolerances is not an issue for me, just the stability of the rig.

Reading onto another, a 30cal rifle is up around 50k PSI, now I am able to put these figures into better perspective.

So im rethinking a few things at least for now, would 5,000 PSI be a reasonable goal to start?

What im stuck on is what conditions would be required ie pre-combustion pressure vs volume? I dont want to play
around with any compressed gasses, only on what can be produced via electrolysis.

violet sin - 25-2-2013 at 19:53

seems like you questions are material based primarily. can 20K psi be contained, yah. but, there are a few things to consider. like the weight of the piston capable of taking the pressure, and the shaft, block n head materials. bearings able to take the heavy beating. it is going to be slamming around at what speeds? is the inertia gonna snap your crank shaft on the back swing? what kind of pre fire pressures do you expect to achieve? you are gonna have to dump a lot of heat, but thin aluminum isn't burst proof and thick steel doesn't shed heat to awesomely. the main thing that seems to say no in my mind is the way you liken the target pressures to gun shots ya know. imagine a little bullet shooting back and forth in there. you think anything is going to stand up to that, that wasn't specifically designed to? how do you balance that so it doesn't shake to pieces... so so many questions.

i believe you mentioned RC car sized motors.. were you hoping to just re-purpose one, or just use it for a pattern? I think you will have trouble compressing "browns gas" at all in an RC motor. lots of 'em use glow plugs not spark plugs. the tiny filament stays hot on the back swing enough to still light on the compression stroke.

I think you are gonna have to get some detailed spec's on the motor you were going to use. a better understanding of the specific dynamics they have going on first. then see how changing the fuel will affect it. are the changes within the tolerances etc. and go from there. man there are TONS of details you are going to have to check... so maybe start investigating the immediate deal breakers before you decide to go further on the RC car scale unless you have a machine shop, training, and materials to make changes to your set up. I would hate to see the thing turn into a frag grenade under the stress... basically it seems like a lot of work for something that is unlikely to work at such a scale. so good luck it sounds like it is going to be a lot of work.

Twospoons - 25-2-2013 at 20:42

An extremely rough calculation based merely on flame temperature and the ideal gas laws (that's why very rough) suggests that to hit 20 kpsi you will have to compress your fuel mix to ~1500 psi before ignition. That's a 100:1 compression ratio, and I suspect I'm under-estimating the compression required. I don't think there's any way you are going to achieve that without pre-ignition problems - the mere act of compression will heat your fuel mix to ignition point well before you hit 1500psi.
And you want to use hydrogen/ oxygen mix - which will likely detonate rather than burn, creating shock waves that will put severe stress on your engine parts.

A non-starter IMO.

NHZ - 25-2-2013 at 23:05

Quote: Originally posted by violet sin  
imagine a little bullet shooting back and forth in there. you think anything is going to stand up to that, that wasn't specifically designed to? how do you balance that so it doesn't shake to pieces... so so many questions.



All excellent points to consider, the one above caught my attention the most. Regarding the setup, I will be machining all the parts in house,
no re-purposing anything all specifically designed to fit

I cannot get into great detail on the design as what im doing to my knowledge has never been tried...

Guns... Lets use a .22 as an example, while the PSI is very great, the weight / resistance is very little, the transfer instantaneous.
I plan on using weight and length of stroke to control some of this. Again only a design in my head right now.

Vibrations and harmonics are all to be considered, perhaps not overcome, but considered none the less. What I was thinking as a start for this,
is multiple cylinders and a well designed crank shaft.

The idea of dealing with the pressure is dependent on the length of the stroke which would be abnormally long.
I want to design this all around the properties of the fuel rather than the other way around / conventional means.
Quote: Originally posted by Twospoons  
An extremely rough calculation based merely on flame temperature and the ideal gas laws (that's why very rough) suggests that to hit 20 kpsi you will have to compress your fuel mix to ~1500 psi before ignition. That's a 100:1 compression ratio, and I suspect I'm under-estimating the compression required. I don't think there's any way you are going to achieve that without pre-ignition problems - the mere act of compression will heat your fuel mix to ignition point well before you hit 1500psi.
And you want to use hydrogen/ oxygen mix - which will likely detonate rather than burn, creating shock waves that will put severe stress on your engine parts.

A non-starter IMO.



Thanks, that helps a bunch.. With this in mind I have one question, what PSI is achievable when a 0psi,
in other words just filling the volume without pressure, how many PSI would be possible? Im looking for
more or less xx PSI @ cu inch..

The concern for shockwaves etc I would try and deal with in the construction, account for it and just experiment
with a variety of setups and materials.

Any thoughts on 'exploding water' as the driving force? This is another topic I would like to touch on if possible. I have
seen some intriguing things done with HV and distilled water..

Endimion17 - 26-2-2013 at 04:29

Quote: Originally posted by NHZ  
When I say HHO, I am simply looking at the natural mix of gases. I apologize you are so offended by this???


"HHO" is a crackpot term used by crackpots to denote a mixture of hydrogen and oxygen ("oxyhydrogen", "knallgas") that supposedly gives more energy than it was invested in liberating it from water by electrolysis, which is of course horseshit. :)

Whenever there's "HHO", there's also "Stanley Meyer", "Brown's gas", "magnet motors", "water cars", and other sophisticated pseudoscientific crap, and sometimes even New Age shit like "orgone".
It's a self-replicating, self-boosting web of lies that uses scientific lingo, but fails to give reproducible results and is in a direct collision with basic natural laws. Ergo, a pseudoscience.

No respectful scientist or chemistry hobbyist will use that term.
The one that uses it is either into pseudoscience, or a layman whose chemistry education comes from filter-free YouTube which, after you type in anything hydrogen related, spits out collosal amounts of crap.

phlogiston - 26-2-2013 at 05:20

If you reformulate them, you are asking valid questions. Although the forum is called 'science'madness, it is predominantly orientated towards chemistry, and people strongly prefer if you use proper chemical terminology (they apparently don't give you some slack because engineer, rather than a chemist).

So, to reformulate it:
1. What you are asking if I am not mistaking is if it is possible to achieve a peak pressure of 20k to 50k psi by isochoric combustion of a 2:1 mixture (by volume) of hydrogen gas and oxygen gas.

2. If you apply a high voltage to water, a very high current will pass, making the water 'explode'. This has nothing to do with electrolysis (@elementcollector1), but is similar to the so-called exploding wire phenomenon, commonly exploited, for instance, to make bridge-wire detonators or nanometer-sized aluminiumpowder. The magnetic forces involved rip the wire/water droplet apart. Again, the question is whether this method can be used to produce a 20k-50k pressure peak in a confined space (constant volume in the timescale of the reaction).

[Edited on 26-2-2013 by phlogiston]

Dr.Bob - 26-2-2013 at 07:48

The issue of building any engine to withstand 20,000 psi and avoiding pre-detonation of a fuel involving hydrogen and oxygen would require engineering and maybe magic, but there is no chemistry involved in that issue. Just building a good diesel engine requires good mechanical engineering, so something many time more PSI is not a chemistry topic as much as an engineering science fiction one. I personally would not want to design anything to mix H2 and O2 at that pressure without a blast shield between me and it.

NHZ - 26-2-2013 at 13:34

It's a self-replicating, self-boosting web of lies that uses scientific lingo, but fails to give reproducible results and is in a direct collision with basic natural laws. Ergo, a pseudoscience.

No respectful scientist or chemistry hobbyist will use that term.
The one that uses it is either into pseudoscience, or a layman whose chemistry education comes from filter-free YouTube which, after you type in anything hydrogen related, spits out collosal amounts of crap.[/rquote]


Understood... As I mentioned, I am no chemist, nor am I a crackpot looking for free energy. I know exactly
what you speak of. I never attended a single chemistry class, it is only now that my hobby has collided
with the need to understand some aspects and the need to remain safe in how I go about things.

When the idea popped into my head, this forum immediately followed as a good starting point.

The idea of using hydrogen and oxygen stems back to 9th grade science and seeing the kick that this fuel
had. Not to mention NASA has been using it for years to launch their shuttles and as far back to the Apollo
missions.

Nothing to do with youtube other than seeing some ridiculous claims. Point taken..
Quote: Originally posted by phlogiston  
If you reformulate them, you are asking valid questions. Although the forum is called 'science'madness, it is predominantly orientated towards chemistry, and people strongly prefer if you use proper chemical terminology (they apparently don't give you some slack because engineer, rather than a chemist).

So, to reformulate it:
1. What you are asking if I am not mistaking is if it is possible to achieve a peak pressure of 20k to 50k psi by isochoric combustion of a 2:1 mixture (by volume) of hydrogen gas and oxygen gas.

2. If you apply a high voltage to water, a very high current will pass, making the water 'explode'. This has nothing to do with electrolysis (@elementcollector1), but is similar to the so-called exploding wire phenomenon, commonly exploited, for instance, to make bridge-wire detonators or nanometer-sized aluminiumpowder. The magnetic forces involved rip the wire/water droplet apart. Again, the question is whether this method can be used to produce a 20k-50k pressure peak in a confined space (constant volume in the timescale of the reaction).

[Edited on 26-2-2013 by phlogiston]



I thought all aspects of innovation would make for a harmonious discussion. Had the forum been named chemforums or the like,
I probably would have expected it. A while back I posted here regarding chlorate cells, and found the responding members to be
quite helpful. Guess this term HHO really irks some. At least now I have a better understanding as to why.

Back on topic, #1 seems to be losing its appeal. I will back burner it for now as I have an idea of its limitations in the volume I plan
on using. All the same, thanks for clearing that up..



Quote: Originally posted by Dr.Bob  
The issue of building any engine to withstand 20,000 psi and avoiding pre-detonation of a fuel involving hydrogen and oxygen would require engineering and maybe magic, but there is no chemistry involved in that issue. Just building a good diesel engine requires good mechanical engineering, so something many time more PSI is not a chemistry topic as much as an engineering science fiction one. I personally would not want to design anything to mix H2 and O2 at that pressure without a blast shield between me and it.



Again, comparing my idea to the conventional ICE has no bearing on this. I am not here asking for a general consensus on
the engineering aspects, only to get baseline numbers and ideas of potential fuels. What you cal 'magic' and 'engineering science fiction'
I call the task at hand. Technology would never move forward if there was no challenge, not to mention a dismissive attitude towards it.

I threw out some numbers to get a better idea of what is possible. I can think of no better place to ask these questions.

With a title like 'sciencemaddness' I figured this topic would be right at home.. Or do you prefer people like Anders Breivik
leeching info on energetics having an ill will toward fellow man, and whoring this forum to his ends?



[Edited on 26-2-2013 by NHZ]

Twospoons - 26-2-2013 at 14:02

Quote: Originally posted by NHZ  

Thanks, that helps a bunch.. With this in mind I have one question, what PSI is achievable when a 0psi,
in other words just filling the volume without pressure, how many PSI would be possible? Im looking for
more or less xx PSI @ cu inch..



Once again, a veryrough calc: starting at 15psi (atmospheric) combustion peak pressure will be around the 100psi mark.
You would get a similar result from using propane and air, without the detonation issue. Combustion volume is irrelevant, as it is assumed constant during the burn.

The problem is that despite the high energy yield from burn H2 and O2, you end up with only 2/3 the number of molecules at the end of the burn, so this reduces the peak pressure.

I think you might find this useful: Gas gun calculator
Its aimed at potato cannon builders, but its a nice way to get a feel for the combustion process. It models combustion of propane, butane and MAPP in a closed volume.

NHZ - 26-2-2013 at 14:38

Quote: Originally posted by Twospoons  
Quote: Originally posted by NHZ  

Thanks, that helps a bunch.. With this in mind I have one question, what PSI is achievable when a 0psi,
in other words just filling the volume without pressure, how many PSI would be possible? Im looking for
more or less xx PSI @ cu inch..



Once again, a veryrough calc: starting at 15psi (atmospheric) combustion peak pressure will be around the 100psi mark.
You would get a similar result from using propane and air, without the detonation issue. Combustion volume is irrelevant, as it is assumed constant during the burn.

The problem is that despite the high energy yield from burn H2 and O2, you end up with only 2/3 the number of molecules at the end of the burn, so this reduces the peak pressure.

I think you might find this useful: Gas gun calculator
Its aimed at potato cannon builders, but its a nice way to get a feel for the combustion process. It models combustion of propane, butane and MAPP in a closed volume.



Im thinking the detonation aspect may work in favor, TBH, it may be the only thing that make use of the 2 gasses viable.
Thanks for the link, that will surly come in handy for other projects as well.

The volumes used for potato cannons are far greater than what I have in mind, so for the gasses I think I will put that on hold
for the time being. In some aspects volume may not matter, but I am thinking of avoiding compressing the unburnt gasses
which limits the potential when burnt. The only thing that may work in favor may be the detonation aspect. Will have to experiment
on this to find my answer. Mind you I have a far better idea now.

I think focusing on 'exploding water' may be the ticket here, or at least my last hope. Is there any way to figure how much
energy can be released from a drop of water hit with HV? From what ive read, the principal of this is based on catastrophic dielectric
breakdown. Salt water obviously has its issues for my application which is why I was looking at the effects of HV on distilled.

What is released when water is hit with HV and a bold current? I always thought just steam, but im guessing that is not all.

[Edited on 26-2-2013 by NHZ]

watson.fawkes - 26-2-2013 at 14:43

Quote: Originally posted by NHZ  
Guess this term HHO really irks some. At least now I have a better understanding as to why.
HHO is perfect marker for crankery. (There are a few others, such as "zero point energy".) Now that you know not to use it, good.

The point that @Twospoons made about 3 molecules --> 2 molecules mean that you're throwing away a fair part of the energy if you try to use the pressure of combustion to drive your engine. On the other hand, the ΔG is plenty high, so you might want to look at Stirling engines instead of internal combustion engines.

phlogiston - 26-2-2013 at 15:08

There are many online descriptions of high voltage discharge setups, in which a capacitor (bank) is charged to some high voltage and then discharged through a wire or other conductive item (eg water), causing it to blow apart.

The energy on a capacitor bank is E = 0.5 * C * V^2
where C is the capacitance, V is the voltage
Some people achieve several kJ per discharge, but you won't need that much. You should calculate it properly yourself (use volume of cylinder and combustion enthalpy of fuel),but I estimate it is of the order of a few 100's of J per cycle.

Here is an online calculator:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capeng.h...

To keep an engine running, you would have to recharge the capacitor bank very quickly ofcourse.


[Edited on 26-2-2013 by phlogiston]

Twospoons - 26-2-2013 at 15:10

Quote: Originally posted by NHZ  


I think focusing on 'exploding water' may be the ticket here, or at least my last hope. Is there any way to figure how much
energy can be released from a drop of water hit with HV?

[Edited on 26-2-2013 by NHZ]


What you can get out is whatever you put in, in electrical energy (minus a bit because physics applies a tax to every energy conversion).
Look up "electrothermal gun".

NHZ - 26-2-2013 at 15:52

Quote: Originally posted by watson.fawkes  
Quote: Originally posted by NHZ  
Guess this term HHO really irks some. At least now I have a better understanding as to why.
HHO is perfect marker for crankery. (There are a few others, such as "zero point energy".) Now that you know not to use it, good.

The point that @Twospoons made about 3 molecules --> 2 molecules mean that you're throwing away a fair part of the energy if you try to use the pressure of combustion to drive your engine. On the other hand, the ΔG is plenty high, so you might want to look at Stirling engines instead of internal combustion engines.



Will do... I at no point considered use in an internal combustion engine. My way of thinking on this
is to design the engine around the fuel, and simply discuss the boundaries.



Quote: Originally posted by phlogiston  
There are many online descriptions of high voltage discharge setups, in which a capacitor (bank) is charged to some high voltage and then discharged through a wire or other conductive item (eg water), causing it to blow apart.

The energy on a capacit bank is E = 0.5 * C * V^2
where C is the capacitance.
Some people achieve several kJ per discharge, but you won't need that much. You should calculate it properly yourself (volume of cylinder + combustion enthalpy of fuel),but I estimite it is of the order of a few 100's of J per cycle.

Here is an online calculator:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capeng.h...

To keep an engine running, you would have to recharge the capacitor bank very quickly of course.



Thats what got my attention. The water in this case is not conductive but a dielectric. The action
sought after is the effect of catastrophic dielectric breakdown of the water which is what peaked
my interest in use of distilled water.

I will do some further reading, thanks for the link.
Quote: Originally posted by Twospoons  
Quote: Originally posted by NHZ  


I think focusing on 'exploding water' may be the ticket here, or at least my last hope. Is there any way to figure how much
energy can be released from a drop of water hit with HV?

[Edited on 26-2-2013 by NHZ]


What you can get out is whatever you put in, in electrical energy (minus a bit because physics applies a tax to every energy conversion).
Look up "electrothermal gun".



Holy crap! I searched thermal gun, some crazy stuff came back including a video. That is some awesome
potential. My only hesitation for my use is the HV aspect, But as mention by another member, I would
have to scale things down to achieve my goals.. Never heard of a electrothermal gun, but that is a great avenue
to venture.

Appreciate it.

Bot0nist - 26-2-2013 at 17:56

Quote:
...do you prefer people like Anders Breivik
leeching info on energetics having an ill will toward fellow man, and whoring this forum to his ends?



[Edited on 26-2-2013 by NHZ][/rquote]

We don't prefere them, and I can't think why you would think so. "Spoonfeeding" about energetics is pretty poorly recieved here, and even if we did censor every thread on recrystalizing ammonium nitrate, it wouldn't even slow down those people with ill will, hurting others.

Sorry for going OT. I find the topic interesting and educational. To far outside of my narrow expertise to meaningfully comment on though, so I will refrian from further derailments.

AJKOER - 26-2-2013 at 18:20

I would move you into another fuel. Hydrogen and Chloride (see my recent thread in Energetic Materials Section of ScienceMadness link: http://www.sciencemadness.org/talk/viewthread.php?tid=23488 ) where HCl is said to have much more power than gasoline/air and 5 times more mechanical energy produced than Hydrogen and Oxygen. Translation, more power and lighter (smaller) engine required.

The problem is to recycle the HCl formed to maintain a closed loop as the Hydrogen chloride gas is corrosive and toxic.

Check out some of my cited references to Patent claiming working prototypes (link: http://www.rexresearch.com/scragg/scragg.htm ).

jock88 - 27-2-2013 at 04:06

<b>THE REAL HHO</b> (Ho, Ho, Ho)


Here's one in a similar vein. It was suppressed by the energy companies many many moons ago. The original author was murdered and his body buried at a secret location.

eng.jpg - 52kB

[Edited on 27-2-2013 by Ripley]

[Edited on 27-2-2013 by jock88]

Morgan - 27-2-2013 at 07:00

Tidbits
"During engine operation the pressure in the main combustion chamber will be around 2900 psi and the temperature will reach 6000 degrees F. Since this is hotter than the boiling point of iron and could vaporize steel, a method of keeping the engine from melting had to be incorporated."
"The low pressure oxidizer turbo pump (LPOT) operating at about 5200 rpm raises the 22 psi oxygen to about 422 psi which is the level required at the inlet of the high pressure oxidizer turbopump (HPOT). The HPOT spinning at nearly 28,000 rpm then raises the pressure to about 4300 psi."
"The low pressure fuel turbo pump operating at nearly 15,000 rpm boosts the liquid hydrogen fuel from a level of 30 psi as it comes from the external tank to 276 psi before it is delivered to the high pressure fuel turbine which is operating at over 30,000 rpm and further boosts the fuel pressure to the operating level of 6515 psi."
http://interspacenews.com/FeatureArticle/tabid/130/Default.a...

High-Pressure Hydrogen Tank Testing
"Improved versions of these tanks made of high-strength composite materials are now used to store hydrogen at higher pressures (5,000 and 10,000 psi) to achieve greater driving range in hydrogen-fueled vehicles.
http://www1.eere.energy.gov/hydrogenandfuelcells/storage/hyd...
70MPa High-Pressure Hydrogen Storage Cylinder
http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/hphsc.ht...

"Oxygen is rarely held at pressures higher than 200 bar / 3000 psi due to the risks of fire triggered by high temperatures caused by adiabatic heating when the gas changes pressure when moving from one vessel to another."
http://en.wikipedia.org/wiki/Oxygen_tank

elementcollector1 - 27-2-2013 at 08:50

Quote: Originally posted by jock88  
<b>THE REAL HHO</b> (Ho, Ho, Ho)


Here's one in a similar vein. It was suppressed by the energy companies many many moons ago. The original author was murdered and his body buried at a secret location.



[Edited on 27-2-2013 by Ripley]



[Edited on 27-2-2013 by jock88]

Please tell me you're joking. I can believe the water freezing due to compression (maybe), but splitting into H2 and O2 due to heat? Bollocks. Utter bollocks.

[Edited on 27-2-2013 by elementcollector1]

Morgan - 27-2-2013 at 11:10

"I think i have heard of this type of freezing activity, but in relation to military submarines. In extreamely cold water (near freezing like at the artice) if the submarine attempts a sudden reverse of direction, the Cavitation of the water around the props will cause the water to rush into the cavitated space, cooling it enough to cause ice buildup around the prop."
"That experiment might be related to cavitation freezing, if the rebound is fast enough to cause cavitation it might be what is causing the freezing effect?"
http://cosmoquest.org/forum/archive/index.php/t-105793.html

"The great French chemist, Antoine Lavoisier, and Charles Meusnier, army officer and inventor, generated hydrogen by passing steam through the red-hot barrel of an iron cannon. The Lavoisier-Meusnier process, with refinements, became the most effective and economical way to obtain hydrogen during the first part of the nineteenth century. Although still in use, the steam-iron method was largely replaced at the start of the twentieth century by two other methods: passing superheated steam over incandescent coke and electrolysis of a dilute solution of caustic soda."
http://history.nasa.gov/SP-4404/app-a1.htm


[Edited on 27-2-2013 by Morgan]

elementcollector1 - 27-2-2013 at 13:38

How exactly does hot iron generate hydrogen?

Xenoid - 27-2-2013 at 16:08

Quote: Originally posted by elementcollector1  
How exactly does hot iron generate hydrogen?


Hydrogen is generated when steam is passed over red hot iron, the iron becoming coated with black magnetite (Fe3O4) in the process!

See Mellor!

Morgan - 27-2-2013 at 16:54

Probably a lot of the noise shown below is from steam vaporization but some unknown amount of oxygen from H20 will react with the hot iron bar. In the case of the red-hot iron piston diagram shown earlier, the iron would have a charge of compressed air and high temperature steam in a confined space.
A good demonstration would be if you could sustain a yellow heat with iron by having a high pressure/high temperature steam but of lower temperature flowing over the iron increasing the temperature by the heat of the reaction.

http://books.google.com/books?id=hCgDAAAAMBAJ&pg=PA51&am...

blacksmith anvil shotgun
http://www.youtube.com/watch?v=4FeGkwo8PsQ

Hydrogen from iron and water
http://pubs.acs.org/doi/abs/10.1021/ed009p916

iron-steam
http://www.grantvillegazette.com/articles/Hydrogen__The_Gas_...

Not the same but this demo came to mind - reactions that can happen when you get the temperature up.
http://www.youtube.com/watch?v=O5v3XxFfUOw

elementcollector1 - 28-2-2013 at 09:36

I think I get it now. The iron takes oxygen from the water, and forms hydrogen.

Endimion17 - 28-2-2013 at 10:22

Quote: Originally posted by elementcollector1  
I think I get it now. The iron takes oxygen from the water, and forms hydrogen.


Or you can say hydrogen was reduced from +1 to 0, and iron was oxidized from 0 to +2 and +3 state.
It's actually one of the well known reactions and essentially the explanation why why water can't be used to extinguish a metal on fire.
It's also the reason why hot nuclear reactor cores must be under water at all times. It's not sufficient to circulate water, there has to be pressure, too. If you lower the pressure, water boils so badly the rods get trapped in a steam bubble, and their zirconium cladding overheats and starts reacting, turning brittle and releasing hydrogen which then has to be vented, and if there's catastrophic release of hydrogen, you're one step away from making an explosion such as the one in Fukushima 1.

That's how Lavoisier was making hydrogen for his experiments, by blowing steam through an iron pipe immersed in fire.
The reaction actually goes in both directions, depending on the conditions. Therefore it's possible to reduce rust to iron powder using hydrogen. In fact, reagent grade iron powder is made that way. That's why it says "ferrum reductum" on the bottle. ;)

[Edited on 28-2-2013 by Endimion17]

KonkreteRocketry - 28-2-2013 at 10:51

u will probably need a very high temperature to keep it self in its gas state