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Thread: DENSITY

  1. #1
    Join Date
    Sep 2000
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    alvarado , tx usa
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    HOW DO YOU FIGURE DENSITY OF AIR WITH PHYSCO CHART

  2. #2
    Join Date
    Jul 2005
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    Read
    http://www.sp.uconn.edu/~mdarre/NE-1...ric_inset.html

    Look at "specific volume" at the very end. Specific volume is 1/density.

    And turn off your caps.

  3. #3
    Join Date
    Apr 2002
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    The specific volume from the p-chart is for dry air only.

    Its units tell you "cubic feet per pound of dry air"

    The chart also gives specific humidity, and the units are "pounds of water per pound of dry air" or 'grains of water per pound of dry air" with a 7000 grains making a pound.

    The specific volume gives how many cubic feet hold one pound of dry air, plus however much water. A specific volume given say '13.33 cubic feet per pound of dry air', tells you there is one pound of air in 13.33 cubic feet, but there is also water vapour in that 13.33 cubic feet.

    If you want the true density of the moist air, then you need to add the mass of water vapour, the specific humidty to that one pound, then divide by the cubic feet in the specific volume.
    The way we build has a greater impact on our comfort, energy consumption and IAQ than any HVAC system we install.

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  4. #4
    Join Date
    Aug 2003
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    I saw this thread title and thought of the line from "Back To The Future" where George McFly is at the soda fountain trying to get Lorraine to go out with him:

    "Lorraine, you are my DENSITY!"



    Oops...thread drift...
    Building Physics Rule #1: Hot flows to cold.


    Building Physics Rule #2:
    Higher air pressure moves toward lower air pressure


    Building Physics Rule #3:
    Higher moisture concentration moves toward lower moisture concentration.

  5. #5
    Join Date
    Jul 2005
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    Originally posted by shophound
    I saw this thread title and thought of the line from "Back To The Future" where George McFly is at the soda fountain trying to get Lorraine to go out with him:

    "Lorraine, you are my DENSITY!"



    Oops...thread drift...
    Awesome movie, the ones that followed sucked...

    HELLO! Anybody in there? McFly?

  6. #6
    Join Date
    Nov 2004
    Location
    SW FL
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    Question Where, then?

    Originally posted by hvac_czar
    [B]
    Is Superheat in New Mexico ?
    Designer Dan
    It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE

    Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

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