What happens when hydrogen meets oxygen?

In summary, the conversation revolves around designing a jet engine that runs on hydrogen and the potential challenges and benefits of this design. The process for producing, transporting, and storing hydrogen is discussed, as well as the use of pulse detonation engines and the feasibility of using hydrogen as a fuel for jet engines. Some concerns are raised about the safety and practicality of this design.
  • #1
Ki Man
539
0
i'm trying to design somewhat of a jet engine but running off of hydrogen... i'll post it on here when I'm don't but before that can anyone tell me what happens to hydrogen when it meets oxygen? does it burn immediately or do you need some type of charge or something to ignite it?

blame my horribly obvious question on my teachers for not teaching me this in school yet :mad:

i know hydorgen is very unstable and will very likely start fire but is it imediate or do you need some type of spark to start it
 
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  • #2
21 views and no replies...

*cricket chirping*
 
  • #3
LOL! Please explain how your jet engine would work in practicality? Is it going to fly through a hydrogen rich atmosphere?
 
  • #4
no. I'm going to try to use it as a fuel for flying around Earth's atmosphere because economically and environmentally hydrogen is a very good alternative to jet fuel. it won't cause pollution and is easy to produce
 
  • #5
maybe not designing a new engine but redesigning/modifying the existing engine designs.
 
  • #6
Ki Man said:
it won't cause pollution and is easy to produce

Elaborate on the process for H2 production, transportation and storage please.
 
  • #7
H2 separates from water when you add electricity. the water separates into hydrogen and oxygen, you can take the hydrogen and then put it into a special tank that won't leak, like the ones used to transport chlorine or something if people are really that worried. when you transport the hydrogen its going to be treated like any other flammable hazmat material and for storage, the tanks can be stored in a medium sized concrete, well ventilated storage shacks about 20 feet wide and be kept a good few dozen yards away from anything else in the area.

maybe not the best way to put things but you get the basic picture right
 
  • #8
You might be better off going with a rocket converted to air-breathing rather than a turbojet. I'm not sure about that, but it seems to me that the existing fuel storage and delivery systems, as well as nozzle design, would be easier to use than trying to alter a system that's designed for liquid fuel.
 
  • #9
yea I've already thought of that its not really that complicated. I've thought of air-breathing rockets before. you can probably meld together the concept of a pulse detonation engine with an air breathing rocket to create a new line of air craft.

i think i have designs for both of them down already. i just need to jot down my horrible horrible sketches now
 
  • #10
can anyone tell me what happens to hydrogen when it meets oxygen? does it burn immediately or do you need some type of charge or something to ignite it?
There is a small amount of energy needed to ignite hydrogen and oxygen. You can have them together without igniting. Something as small as a static electric spark is sufficient to ignite them.
 
  • #11
Ki Man said:
tell me what happens to hydrogen when it meets oxygen? does it burn immediately or do you need some type of charge or something to ignite it?
It needs to reach the appropriate temperature to burn.

Ki Man said:
i know hydorgen is very unstable and will very likely start fire but is it imediate or do you need some type of spark to start it

In jet engines, some special provisions are made so that when the flame starts, it does not blow out. Initially a source of energy to ignite the mixture of H and 02 is needed in jets but after that the flame provides that energy.


Why do you want to make an H2 powered jet. It will not decrease pollution because H2 itself needs electricity to make (unless you are not using electrolysis). Electricity comes from coal. And storage is a huge problem with H2.


As for pulse detonation engines, I would seriously advise you against experimenting with them unless you have access to a proper lab. Should a disaster occur, it may be fatal.
 
  • #12
sid_galt said:
It needs to reach the appropriate temperature to burn.



In jet engines, some special provisions are made so that when the flame starts, it does not blow out. Initially a source of energy to ignite the mixture of H and 02 is needed in jets but after that the flame provides that energy.


Why do you want to make an H2 powered jet. It will not decrease pollution because H2 itself needs electricity to make (unless you are not using electrolysis). Electricity comes from coal. And storage is a huge problem with H2.


As for pulse detonation engines, I would seriously advise you against experimenting with them unless you have access to a proper lab. Should a disaster occur, it may be fatal.



Yeah i'd tend to agree with this statement. H2 is a poor choice for fueling(at least in natural aspirated engines, to which are not in a more "durable" enviroment..IE an automobile engine). If i were you I'd suggest looking at other petrolum based designs, or further into the RAM/SCRAM jet region. I'm not saying your desgin is impossible, but a lot of research and money has gone into Hydrogen. If it was a feasble idea to have a jet engine run on it, there be talk about it in the news and such. I'd do a search and see his anyone has conducted expirments with such an idea, and then go from there.
 
  • #13
Ki Man said:
H2 separates from water when you add electricity. the water separates into hydrogen and oxygen, you can take the hydrogen and then put it into a special tank that won't leak, like the ones used to transport chlorine or something if people are really that worried. when you transport the hydrogen its going to be treated like any other flammable hazmat material and for storage, the tanks can be stored in a medium sized concrete, well ventilated storage shacks about 20 feet wide and be kept a good few dozen yards away from anything else in the area.

maybe not the best way to put things but you get the basic picture right

I asked my question(s) for a reason. 1) H2 is a little hard to store. H2 molecules are small---small enough to migrate through a crystal lattice with some ease---and as such lopng-term storage can be a problem. Another problem with the size of the H2 molecule is a corrosion mechanism called hydrogen embrittlement. Essentially, H2 will leech into a material(especially when the material is heated) and change the xtal structure resulting in a more brittle material.

As for production, it requires electricity, as you said, so simply converting to a hydrogen buring does not mean less pollution. The source of electricity used to split the H2O may actually pollute more then a conventional engine---I have an oil fired emergency substation near my house as an example.

Well, good luck with your project and keep H2 corrosion in the back of your mind.

[edit] I wrote this last night but I closed my laptop before it posted. I opened it today and my laptop left off where it was before I closed it so some information was repeated. Sorry.
 
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  • #14
To chime in here and reiterate what has already been said, you need a spark source to initiate the combustion of H2 and air. We use small torches as a start mechanism in testing on our engines that do not have igniters in them. Of course, I am sure that since you are even thinking about H2 that you are well versed in the safety precautions required with H2 usage.

BTW...what exactly is "somewhat of a jet engine?"
 
  • #15
To reiterate again but focus the attention on the real problem, the pollution given off by jets seems really bad if you watch a plane taking off and see the giant plume of smoke with visible particulate matter.

But overall electricity generation creates a LOT more bad pollution than aircraft and cars and ships and forest fires and just about everything else put together. The media likes to focus on a car tailpipe, but the real problem is in the coal power plants and the places with fast growth like China are going to really complicate the problem.

So its like a sad irony that the typical enviromentalist answer to pollution is electric cars or a hydrogen economy without a plan for clean generation that makes sense. I personally like the idea of distributed solar but it has its own problems in the current technology where the construction of the silicon panel has a large electricity requirement to produce the panels in the first place.

A complex problem like energy management needs a comprehensive solution and those don't fit into media soundbites and campaign pledges very well at all.
 
  • #16
i have an idea that will generate electricity without pollution, but i still need to test it. its my science fair project. it'll be done in a few weeks.

AND hydrogen is a bad idea now that i think about it i was just considering the possiblities.
 
  • #17
Ki Man said:
i have an idea that will generate electricity without pollution, but i still need to test it.

The best way to generate electricity without high levels of pollution is nuclear power.

As for electricity without pollution, what fuel will you be using? I hope you are not talking about some idea which violates the laws of thermodynamics.

Ki Man said:
AND hydrogen is a bad idea now that i think about it i was just considering the possiblities.
Don't give up. There is intensive research going on to solve the storage problems of hydrogen because of its potential to be used in fuel cells.
 
  • #18
As for electricity without pollution, what fuel will you be using? I hope you are not talking about some idea which violates the laws of thermodynamics.

My solution is rickshaws, lots of them. :-)
 
  • #19
technically i don't think it breaks any laws of thermodynamics. if it works i'll post it on here ASAP and nobody take my idea i have at least 6 witnesses that will testify that it was mine. as long as the Earth is in tact it will work.

i think there's a 75% chance of it working. i'll see if i can get it to work this weekend.
 
  • #20
if your idea works will it be able to provide large amounts of electricity or atleat enough for one household? That would be neat if it hasnt been thought of before and it WORKs.
 
  • #21
hmm... i have some free time on my hands right now... maybe i can get it done tonight.

how much power it will produce depends on the scale of it. i will explain more later. i am not giving anything away right now.
 
  • #22
well get on it lol! my brother made an electric generator for his science fair but his was just a windmill with copper coils powerd by a hair dryer. (since he wouldn't be able to make wind blow in a classroom!)
 
  • #23
darn. air leaks have stopped progress for today. i need to find a better way to stop air bubbles, but I'm only using household items because i lack the proper supplies. my dad won't let me go home depot and get pipes and junk so I'm stuck using straws, a waterbottle, and chewing gum. i think I've solved one of the air bubble leaking areas so i just need to do the same thing to the other area and it should work.
 
  • #24
Ki Man said:
my dad won't let me go home depot and get pipes and junk
Tell him that you have to disassemble his VCR for parts and he'll drive you there. :devil:
By the way, if the formula hasn't changed much in the last 40 years, Juicy Fruit gum hardens to the consistency of JB Weld and seals just about anything.
 
  • #25
hmm... juicy fruit gum?
 
  • #26
Ki Man said:
i'm trying to design somewhat of a jet engine but running off of hydrogen... i'll post it on here when I'm don't but before that can anyone tell me what happens to hydrogen when it meets oxygen? does it burn immediately or do you need some type of charge or something to ignite it?
Hypergolic propellants are a fuel and oxydizer which ignite spontaneously on contact with each other. Hydrogen is not Hypergolic but has a very low activation energy and is exstremely exthothermic in its reaction with oxigen. Storage is the main problem with hydrogen as a liquid fuel since it needs to be cryogenically stored and it has a very low molecular weight. (Ask yourself why the spaceshuttle main fule tank is so big in comparison to the SRB's)
 
  • #27
For safe storage of hydrogen, I'd be inclined to go with magnesium hydride. It traps 1g/cc when chilled, and releases it when heated. Much cheaper, but less efficient, is iron-titanium hydride.
 
  • #28
Ki Man said:
hmm... juicy fruit gum?
A quite tasty concoction of Wrigleys.
 
  • #29
straws are very bad. I'm going to force my dad into taking me to home depot this weekend somehow and buy the proper platic tubes and maybe some kind of small tank because i can't seem to get the waterbottle just right.

science fair projects aren't going the way they should. this isn't much of a science fair... its more like creating a presentation on some kind of stupid poll like other groups and having the teacher grade you on your use of the scientfic method. we are the most original group with our concept. everyone else is doing pointless studies like, which works better, gatorade or water.

when they said science fair i was thinking more science and less... pointless data and charts that holds tons of room for human error.

are all science fairs like this or is it just the best my peers can come up with at our level
 
  • #30
Ki Man - I think it sounds like you are expecting to have an Earth'shattering discovery with your science fair project. Let's say you did, if you couldn't tell people about it, what good would it do? There are many examples in history of people with insights that went unused for years or were forgotten when someone else came along and did a better job of presenting their findings. Da Vinci is probably one of the most cited for this, a lot of his inventions were practical long before they were ever used. How different would life for us be if his plans for scuba or parachutes or whatever had been implemented during his lifetime?

The expectation with a science fair is not to create something new but instead to learn how to do something. Correctly demonstrating the ability to use the scientific method to determine A instead of B and explaining those findings is very important, even if its about something some people would be aware of or could find published already.

Regardless, would you not want to practice the process with something small first, even if less than a completely new perspective on a problem that needs solving? That is the point, that if you did discover something new and insightful, that you could explain it in a way that would allow your discovery to accepted by others and utilized whether it be for the common good or commercial success.
 
  • #31
i'm not expecting anything Earth'shattering from my project or from the other projects, i just think the other projects could have aimed a bit higher than water vs gatorade, which is an important study, nonetheless, but is very highly cliched as an expirement
 
  • #32
On the other hand, you could try using Gatorade as a fuel. How well does it burn compared to water?:biggrin:
 
  • #33
Ever seen the guy with the "Rocket backpack" he's using Silver Ag as a catalyst, and reacting Hydrogen Peroxide H2O2 to achieve a good discharge rate, for thrust, but caution is needed as the temperature can easily hit 750° F
 
  • #34
Oh Yes, Gatorade is simply the "Cure" (Discovered) for Dehydration, a Liter of Water, a Handfull of Sugar, and a Pinch of Salt .. .. .. Roughly <plus coloring and Vitamin C etc.>
 

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