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Engine not using air

  1. Mar 21, 2008 #1
    Hi, i just want to know if its possible to run an internal combustion engine on liquid oxygen instead of air
  2. jcsd
  3. Mar 21, 2008 #2


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    Seems to me, you'll expend a lot of energy getting the oxygen up to temperature or it will quash ignition.
  4. Mar 22, 2008 #3
    I believe there used to be some soviet submarines that did something similar to this. Unfortunately it seemed that during the cold war.... soviet engineering + safety = what?
    So many of them had catastrophic fires killing many submariners and the idea was scrapped.
  5. Mar 22, 2008 #4
    Sure. You could use the hot exhaust manifold to boil the LOX and preheat it. The nitrogen in the air does nothing useful except slightly cool and dilute the burning process, and you might need to fiddle with that a little. But, the idea would work OK - just makes things complicated and expensive.
  6. Mar 22, 2008 #5
    thanks for the reply
    i was having a idea to fit it on a commercial submarine so it doesn't have to pop up every 30 seconds
  7. Mar 22, 2008 #6
    Well, the good old USSR thought of it too....there were some very big problems with it's implementation too...by having LOX on a submarine it gave a readily available source of O2 for fires which was the main down side.
  8. Mar 22, 2008 #7
    I think simple compressed air, such as in a scuba tank, would be sufficient, not to mention less dangerous. Of cource, the volume would be prohibitive from a practical standpoint. Scuba tanks generally hold only about 80-100 cubic feet at roughly 2500-3500 psi.
  9. Mar 22, 2008 #8


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    Which is why it wouldn't be sufficient. Lose the nitrogen, and you increase your oxygen by a factor of 4.
  10. Mar 23, 2008 #9


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    The German Navy designed and built a fuel cell submarine about 8 years ago having liquid oxygen storage. Hydrogen is stored in metal hydride canisters. Here's a couple of references if you're interested.

    http://www2.sea.siemens.com/NR/rdonlyres/D3201AC8-C746-4EC8-975A-64E607662195/0/SiemensPresentsFuelCellattheAdvanceNavalPropulsionSymposium.pdf [Broken]
    Last edited by a moderator: May 3, 2017
  11. Mar 23, 2008 #10
    I suppose you might use a snorkel?
  12. Mar 23, 2008 #11


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    Have you ever talked to anyone that has worked with pure O2? How about done any research? The HUGE thing about pure O2 is that, for your application, you would have to develop an engine that had a completely different form of lubrication. Pure O2 can not come into contact with any form of petroleum. Seals would also have to be changed. Anything that comes in contact with pure O2 in an industrial setting has to be specially cleaned and packaged. You would also have to be knowledgeable in the use of valves. Pure O2 can use as its source for combustion, the very piping it is contained in. One of the main forms of disaster is through compression ignition fires in pure O2 systems.

    What you are proposing is not an easy task and is very dangerous.
  13. Apr 7, 2008 #12
    Pure O2 will increase your adiabatic flame temperature (probably to the melting point of many of your engine parts).
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