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  1. Standard member sonhouse
    Fast and Curious
    24 Jan '11 20:48
    http://www.physorg.com/news/2011-01-split-cycle-efficient-traditional-combustion.html

    They separate the compression cycle from the combustion cycle using one piston for compression only and another for combustion. Lower emissions of NOX and CO2, more complete combustion, firing after top dead center, a great trick and combustion ratios of over 100 to 1!
  2. 25 Jan '11 19:49
    Originally posted by sonhouse
    http://www.physorg.com/news/2011-01-split-cycle-efficient-traditional-combustion.html

    They separate the compression cycle from the combustion cycle using one piston for compression only and another for combustion. Lower emissions of NOX and CO2, more complete combustion, firing after top dead center, a great trick and combustion ratios of over 100 to 1!
    I don't know why having a separate chamber would make any difference.

    You could make a compression ratio of 100 for any engine if you are willing to modify it enough and use a modified fuel.
    I would think diesel or regular unleaded fuel would be unstable at that compression anyway, since a diesel engine only compresses up to 20 and it autoignites.
  3. Standard member sonhouse
    Fast and Curious
    25 Jan '11 20:50
    Originally posted by mlprior
    I don't know why having a separate chamber would make any difference.

    You could make a compression ratio of 100 for any engine if you are willing to modify it enough and use a modified fuel.
    I would think diesel or regular unleaded fuel would be unstable at that compression anyway, since a diesel engine only compresses up to 20 and it autoignites.
    What makes 100 to 1 possible is compression and injection happens with a lot more turbulence and mixes a lot faster and ignition after top dead center. Did you read the article or look at the video's?
  4. 26 Jan '11 05:00 / 1 edit
    Originally posted by sonhouse
    What makes 100 to 1 possible is compression and injection happens with a lot more turbulence and mixes a lot faster and ignition after top dead center. Did you read the article or look at the video's?
    Neither....too busy.



    Sorry.

    Just spewing out what I know about autoignition of hydrocarbons and I do know that compressing a parafin 100X would surely cause it to autoignite. Sounds like a very dangerous situation.
  5. Standard member sonhouse
    Fast and Curious
    27 Jan '11 03:24
    Originally posted by mlprior
    Neither....too busy.



    Sorry.

    Just spewing out what I know about autoignition of hydrocarbons and I do know that compressing a parafin 100X would surely cause it to autoignite. Sounds like a very dangerous situation.
    100 X compression would be 1470 psi, I don't think they actually get that high. They are talking about 2.5 bar which would be under 40 psi. Not sure where they get that 100X from. They used a figure of 1.5 bar as the pressure usually used in a supercharger or blower.