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Trying to design an engine

  1. Sep 25, 2005 #1
    i'm trying to design somewhat of a jet engine but running off of hydrogen... i'll post it on here when i'm dont 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
  2. jcsd
  3. Sep 25, 2005 #2
    21 views and no replies...

    *cricket chirping*
  4. Sep 25, 2005 #3
    LOL! Please explain how your jet engine would work in practicality? Is it going to fly through a hydrogen rich atmosphere?
  5. Sep 25, 2005 #4
    no. i'm going to try to use it as a fuel for flying around earths atmosphere because economically and environmentally hydrogen is a very good alternative to jet fuel. it wont cause pollution and is easy to produce
  6. Sep 25, 2005 #5
    maybe not designing a new engine but redesigning/modifying the existing engine designs.
  7. Sep 25, 2005 #6
    Elaborate on the process for H2 production, transportation and storage please.
  8. Sep 25, 2005 #7
    H2 seperates from water when you add electricity. the water seperates into hydrogen and oxygen, you can take the hydrogen and then put it into a special tank that wont 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
  9. Sep 25, 2005 #8


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    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.
  10. Sep 25, 2005 #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
  11. Sep 26, 2005 #10


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    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.
  12. Sep 26, 2005 #11
    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.
  13. Sep 26, 2005 #12

    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 alot 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.
  14. Sep 26, 2005 #13
    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.
    Last edited: Sep 26, 2005
  15. Sep 26, 2005 #14


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    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?"
  16. Sep 26, 2005 #15


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    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.
  17. Sep 26, 2005 #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.
  18. Sep 26, 2005 #17
    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.

    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.
  19. Sep 26, 2005 #18
    My solution is rickshaws, lots of them. :-)
  20. Sep 27, 2005 #19
    technically i dont 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 theres a 75% chance of it working. i'll see if i can get it to work this weekend.
  21. Sep 27, 2005 #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.
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