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Pressurized Tank

  1. May 25, 2007 #1
    I am trying to figure out how to equate hole size to pressure loss/time for a closed tank. Here's the scenario:

    300 L closed tank
    Pressurized to 20 psig with air
    Pressure loss is 1 psi over a time period of 1 hour
    Temperature is 30 deg. C

    How can I relate hole size to this pressure loss? Can assume ideal gas...just need a rough estimate/ball park answer.
  2. jcsd
  3. May 25, 2007 #2


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    Homework Helper
    Gold Member

    Use the conservation of mass (ie, continuity equation), the equation of state and an energy balance (ie, bernoulli equation)
  4. May 25, 2007 #3


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    Staff: Mentor

    Right - and whatever you get from that, double it, since the nozzle efficiency is probably only 50%.
  5. May 25, 2007 #4


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    Science Advisor

    Not to mention it will be sonic coming out of any hole that will allow a back pressure that large.
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