Need help on model HHO propulsion systems

  • #1
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Hey all, Lime here.

I've been getting into HHO for a while, and I think I almost have my DIY generator up and running (waiting on eBay 18650 batteries). I was thinking a fun little project is to play around with a few concepts with my new found combustion source. Anybody here know a good way to get started in HHO propulsion?

P.S. it doesn't have to leave the ground. Just a bit of fun is all.

Edit:
The system would be connected to the station on ground, so no worries about storing it onboard any crafts.
 

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  • #2
berkeman
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Sorry, what is ##H_2O## propulsion? You are using your battery to make ##H_2## and then burning it for propulsion?
 
  • #3
jrmichler
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As long as you expect to just have a little fun, you should be OK. However, if you expect to actually make it work, you are out of luck. HHO is breaking water into hydrogen and oxygen, then combining those two gases back into water. Both steps are less than 100% efficient, so the useful energy out must be less than the energy in from the battery. In the real world, the useful energy out is much less than the energy in.

There is nothing new about HHO. It has been around since electricity, electrolysis, and internal combustion engines were invented. It has never worked, but the free energy people continue to claim (without evidence) benefits from it.

The calculation of how much gas can be electrolyzed from water given the energy stored in one or more batteries can be calculated from high school physics. The energy of combustion is high school chemistry. Both of those processes have losses. Conversion of the energy of combustion to thrust or lift has even larger losses.

If you want to convert battery energy into lift, putting the battery into a drone will be far more efficient than converting battery energy into gas, then gas back to water.

You can measure the efficiency of your electrolysis process by measuring the volume of gas produced, and comparing the amount that would be produced if the process was 100% efficient. That could be a fun little experiment.
 
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  • #4
russ_watters
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Hey all, Lime here.

I've been getting into HHO for a while, and I think I almost have my DIY generator up and running (waiting on eBay 18650 batteries). I was thinking a fun little project is to play around with a few concepts with my new found combustion source. Anybody here know a good way to get started in HHO propulsion?

P.S. it doesn't have to leave the ground. Just a bit of fun is all.

Edit:
The system would be connected to the station on ground, so no worries about storing it onboard any crafts.
Hi. This is your hobby so I'm not sure we can tell you what you should do with it, and you haven't given us much to go on. Do you have any idea of what sort of propulsion you want to make? Are you hoping to build a rocket/torch? Are you hoping for continuous propulsion using a battery-powered rocket? How many batteries? Presumably you read about this somewhere or watched some youtube videos about it, so help us out here -- what are you trying to do?
 
  • #5
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Sorry, what is ##H_2O## propulsion? You are using your battery to make ##H_2## and then burning it for propulsion?
Yep yep,
Basically, it's electrolysis of water. When the molecule separates, it forms H2 and O2 gas, which can then be burned for propulsion.
Also I just realized a tad mistake in the post. HHO doesn't really exist in chemistry, but it's usually referred to H2 and O2 gases mix. My apologies for that.
 
  • #6
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Hi. This is your hobby so I'm not sure we can tell you what you should do with it, and you haven't given us much to go on. Do you have any idea of what sort of propulsion you want to make? Are you hoping to build a rocket/torch? Are you hoping for continuous propulsion using a battery-powered rocket? How many batteries? Presumably you read about this somewhere or watched some youtube videos about it, so help us out here -- what are you trying to do?

Ah, my apologies for that mate. Honestly, I am currently thinking of using the H2 and O2 gases in a miniature rocket. Not entirely sure how to go about it to be honest, and it would be pretty nice if there were some suggestions relating to rocketry.
All suggestions relating to combustion would help though!
 
  • #7
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As long as you expect to just have a little fun, you should be OK. However, if you expect to actually make it work, you are out of luck. HHO is breaking water into hydrogen and oxygen, then combining those two gases back into water. Both steps are less than 100% efficient, so the useful energy out must be less than the energy in from the battery. In the real world, the useful energy out is much less than the energy in.

There is nothing new about HHO. It has been around since electricity, electrolysis, and internal combustion engines were invented. It has never worked, but the free energy people continue to claim (without evidence) benefits from it.

The calculation of how much gas can be electrolyzed from water given the energy stored in one or more batteries can be calculated from high school physics. The energy of combustion is high school chemistry. Both of those processes have losses. Conversion of the energy of combustion to thrust or lift has even larger losses.

If you want to convert battery energy into lift, putting the battery into a drone will be far more efficient than converting battery energy into gas, then gas back to water.

You can measure the efficiency of your electrolysis process by measuring the volume of gas produced, and comparing the amount that would be produced if the process was 100% efficient. That could be a fun little experiment.

Oh yeah totally mate, I just use HHO because that's the most available and cleanest combustion I can get my hands on at the moment. Would love to experiment with some dirtier fuels, but I don't trust my wallet to do that just quite yet. Plus some key advantages, like having an oxidizer at the ready and not having to worry about storing these gases is also fun. Some other fun stuff, like lighter-than-air crafts are also a fun idea. Well. Assuming they don't explode that is.

Speaking of explosions, having a relatively pure concentration of HHO gas would be provide at least a few known variables than trying to DIY some other fuels.

Would love to have a go with some other DIY fuels, like the ones listed below:
http://opengarages.org/index.php/DIY_fuel_production

But just stuck with HHO for the reasons above. Also, I'd love to become a better applicant to the propulsions laboratory at this college I'm heading to, so having a go at these things is definitely something I'd like to try.

-------------------------------------------------------------------------------------------------------------------------------------

I know you probably meant a pure HHO engine on its own, but while we're here on this topic;

I've been a tad confused between the efficiencies brought by combining gas and HHO. So there are a few journal entries like:

https://reader.elsevier.com/reader/...egion=us-east-1&originCreation=20210528183453

Claim HHO and gas combinations would increase overall engine performance. And of course, some drawbacks as well. Really, pick your poison on these.

Of course, I think we both agree a purely HHO system would not be efficient. However, would you perhaps know if the addition of HHO and other gases would be "better" for combustion? I mean, there are some metrics on what constitutes "better," such as waste gas emissions and engine performance. But in terms of the combination of gases, would it be better?

Sorry in advance for the noob questions. Just trying to sort through all these random contradicting sites.
 
  • #8
Vanadium 50
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I don't get what HHO is and how it differs from H2O.

What exactly are you trying to do? Electrolyze water, put the H2 and O2 mixture into a rocket and light it? That will work, but probably not as well as you think.

Say we have 100 cc of gas. That's about 6cc of hydrogen and 94 cc of O2, and the whole thing weighs about 1.5 mg. That will produce about 20 J of energy when it combines to make steam at STP. The maximum momentum it will produce shooting out the back end is about 750 g cm/s. That is also the maximum momentum the rocket can pick up. This is 1/40 of the impulse of the smallest model rocket engine you can buy.
 
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  • #9
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If I'm understanding the info in the links you provided, then HHO is a mixture of hydrogen and oxygen gas produced by electrolysis, as opposed to separating the gases when produced. One link seems to describe feeding the mixture directly into the intake manifold of a gasoline engine, which doesn't sound too bad on its face, but surely you are not thinking of storing this stuff, or worse yet trying to compress it to feed a rocket engine?
 
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  • #10
Vanadium 50
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worse yet trying to compress it to feed a rocket engine
The technical term for this is "very bad idea".
 
  • #11
berkeman
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If I'm understanding the info in the links you provided, then HHO is a mixture of hydrogen and oxygen gas
Oh, wait. I guess I misunderstood (I haven't been keeping up with the thread very well). So when the OP writes HHO, he really means an ##H_2 + O_2## mixture of gasses? Then why not write it as HHOO? Maybe because that rhymes with "woo"?
 
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  • #12
jrmichler
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HHO, AKA Brown's gas, is fringe science, AKA pseudoscience, AKA junk science. These terms are used by technically illiterate people and con artists to describe oxyhydrogen. Oxyhydrogen is a mixture of oxygen and hydrogen. It is easily generated by electrolysis of water without separating the two gases. Con artists claim that it improves gas mileage when generated and used in internal combustion engines.

I'd love to become a better applicant to the propulsions laboratory at this college I'm heading to
If true, you would be well advised to stay far away from scams like HHO. Playing around with HHO just tells them that you did not learn basic chemistry, physics, and thermodynamics. The fact that you mentioned using it in a rocket just shows that you did not do the simplest search. If you had, you would know that compressing oxyhydrogen makes it explode.

The one thing in your favor is that you mentioned powering your electrolyzer with a battery. The amount of gas generated will merely ##_{pop}## instead of BLAM.
 
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  • #13
berkeman
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compressing oxyhydrogen makes it explode
I learn something new on PF every day! :wink: :oops:
 
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  • #14
Vanadium 50
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compressing oxyhydrogen makes it explode.
I learn something new on PF every day!
Well, I think technically pressure makes it more likely to explode. If you do it slowly enough, you probably can reach high pressures. Most of the time anyway.

A fast shock and it will be like a diesel engine's ignition, and then a big kaboom, that's for sure.
 
  • #15
berkeman
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Oh, wait. I guess I misunderstood (I haven't been keeping up with the thread very well). So when the OP writes HHO, he really means an ##H_2 + O_2## mixture of gasses?

1622417946694.png

https://www.physicsforums.com/threads/collection-of-lame-jokes.25301/page-388#post-6497970
 
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  • #17
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Oh, wait. I guess I misunderstood (I haven't been keeping up with the thread very well). So when the OP writes HHO, he really means an ##H_2 + O_2## mixture of gasses? Then why not write it as HHOO? Maybe because that rhymes with "woo"?
Haha I like that comparison. It stands for hydrogen-hydrogen-oxygen and is a colloquial term for oxyhydrogen gas. I agree though, I'ma call it WOOOOOO gas from now on in my everyday life. Not to be confused with laughing gas that is

I don't get what HHO is and how it differs from H2O.

What exactly are you trying to do? Electrolyze water, put the H2 and O2 mixture into a rocket and light it? That will work, but probably not as well as you think.

Say we have 100 cc of gas. That's about 6cc of hydrogen and 94 cc of O2, and the whole thing weighs about 1.5 mg. That will produce about 20 J of energy when it combines to make steam at STP. The maximum momentum it will produce shooting out the back end is about 750 g cm/s. That is also the maximum momentum the rocket can pick up. This is 1/40 of the impulse of the smallest model rocket engine you can buy.

@ Vanadium 50
Oh I love the analogy, but yes you're correct. It's mainly just a way to see what a bit of combustion looks like is all. By the way, the stochiometric mixture of 2:1 H2 to O2 respectively is usually what most do, but I'm doing 3:1 mixture. So it'd be more like 75cc H2 and 25cc O2, which is still going to produce meh results.

Should be fine to look at the pretty flames though :D
 
  • #18
berkeman
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This thread has attracted some fringe science posts, and will be closed now (after the posts were cleaned up).
 
  • #19
DrClaude
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Should be fine to look at the pretty flames though :D
Post-lockdown comment by @Tom.G:
Sorry, Hydrogen flames are invisible, no Carbon to incandesce.
 
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