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Liquified Nitrogen!

  1. Jun 10, 2010 #1
    I know the undeniable substantial applications of cryogenics fluids in engg. sciences, but can't hold on how these fluids are cooled or liquifed from gaseous state??
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  3. Jun 10, 2010 #2


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    At what pressure would nitrogen exist as a liquid at RT? How about at -80C?
  4. Jun 12, 2010 #3

    definitely not at RT, what i think!!
    boiling point of N2 -196 C
  5. Jun 12, 2010 #4


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    It's done by utilizing the ideal gas law: when you pressurize a gas it heats up. If you cool it back to room temperature while maintaining the pressure, then let it expand through a nozzle, it cools down. Do that enough and you'll liquify it.
  6. Jun 21, 2010 #5

    wish could have link for detailed citation
  7. Jun 21, 2010 #6


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  8. Jun 22, 2010 #7


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    Last edited by a moderator: Apr 25, 2017
  9. Jul 31, 2010 #8
    The Joule Thompson effect will get you a temperature change by expanding through a nozzle, but for added cooling, expand in an expansion engine. Gas that does work loses energy ;-)
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