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I guess we have all been had.

Discussion in 'Gen 2 Prius Fuel Economy' started by billynjoanna, Dec 26, 2007.

  1. madler

    madler Member

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    I think you're missing the claim. They are not claiming a perpetual motion machine by somehow recovering more energy from the hydrogen itself. The claim is that a small proportion of injected hydrogen improves the combustion of the diesel fuel. The hydrogen itself would be burned as well, but that is inconsequential. The efficiency gain would come from burning more of the diesel that would otherwise be blown out the stack.

    I don't know whether this actually works or not, but the claim does not violate any laws of physics.
     
  2. priusincc

    priusincc Member

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    I remember these old ads too. The idea seems to surface every decade or so. P.T. Barnum was right.
     
  3. aaf709

    aaf709 Ravenpaw of ThunderClan

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    This reminds me of the water vapor injector my father had on his 1964 Plymouth Fury. The idea was that the engine works better in a fog so by injecting water into the carburetor would duplicate it.
     
  4. donee

    donee New Member

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    Hi aaf709,

    This is yet another invalid application to gas cars from valid uses in different types of engines. Specifically Brayton cycle axial flow turbines is where water injection works. Its acts like a phase-change intercooler to cool down the compressed air, and get better volumetric efficiency into the combustors. Just from the sound of that the amount of water injection is critical to avoid to much extra volume from the expanding water vapor.

    Older B52's in particular used this technique for extra take-off power.
     
  5. patsparks

    patsparks An Aussie perspective

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    My boss from a former job had water spraying into the turbo he fitted to his early Celica. It sprayed right into the middle of the turbine to break the water into a mist, it had a genuine power increase but I believe that was due to cooling of compressed air. This was before intercoolers were popular. He would mix about 5% alcohol into the water for more power again.
     
  6. JimN

    JimN Let the games begin!

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    In 1940 RAF Spitfires had water injection engines. I'm pretty sure Grumman's fighters (and maybe Mustangs) were water injected as well.
     
  7. brad_rules_man

    brad_rules_man Hybrid electric revolutionizer

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    There are electrolysis versions of hydrogen/water engines. This one, however is a total rip off!
     
  8. diamondlarry

    diamondlarry EPA MPG #'s killer

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    I thought I remembered hearing that F4U Corsairs had it too. I used to be a WW2 buff when I was in Junior High and that was a looong time ago and I may be having a senior moment.:D
     
  9. Grunthos

    Grunthos Senior Azgoth Poetmaster

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    So if I understand the nature of the ad, I can get hidden energy from my empty gas tank, right? (All I need to do is fill it with gas.)
     
  10. brad_rules_man

    brad_rules_man Hybrid electric revolutionizer

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    Actually, back in the day I believe on certain planes they used to inject just a tiny bit of moisture into a piston in between firings, basically utilizing the hot pistons as a steam engine also, there is some to be gained in that, however I think it wears out the motor quicker? I remember there was some downside to it and it didn't work out well. I guess the steam probably doesn't do well for modern day exhaust systems...
     
  11. diamondlarry

    diamondlarry EPA MPG #'s killer

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    It could very well have made the motor wear out quicker. It seems to me that the water was only injected in emergencies when the extra power was needed to shake someone off their tale during a dogfight in which case engine wear was probably not a big concern.