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Compressed air for power generation
Last Post 11 Feb 2013 12:36 PM by james.wolf. 0 Replies.
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11 Feb 2013 12:36 PM
    I am trying to use compressed air to recharge a battery bank by driving an air motor coupled to an alternator.

    Compressed air cylinder
    Size -50
    Service pressure 2900 psi
    Cubic feet 335
    Internal water volume 3051 cubic inches
    The central question #1 is how long can I release pressure at 80 psi?

    Simple pressure/volume calculations don't seem to produce a good result
    The big variables are pressure/volume/temperature effects..especially temperature?
    I'm talking about an industrial compressed air cylinder filled in the normal manner.(adibiatic??)
    When the air is expelled it is cold so the problem takes on two faces.
    First without and then with expanding the air by heating it.
    I'm thinking the calculation without expanding should be fairly simple but I lack the ability
    Method of expansion would be by running it through a finned coil with a blower to extract cold and heat/expand the air in the coil.

    Rotary Vane Air Motor,
    0.4 Output HP, Max RPM 2000, Torque 14.0 In-Lbs, Max Air Consumption 30 CFM, Max Torque 20.0 In-Lb, Max Air Pressure 80 PSI, Inlet/Outlet NPT 1/4 In

    Reduced via pulleys to stay within air motor max torque

    Bottom line with this set up, how much power in kw can I produce with one tank of compressed air?

    If you have interest in helping me please answer through this site or directly at
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