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Thread: m=V/v

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    m=V/v



    Anyone familiar with the relationship between mass flow rate and volume flow rate divided by velocity? m = V/v. Im probably mistaking something though. Thanks.

    The word "gasoline" is a mistake in the image, should be "air".
    mvv.png
    Last edited by seanf; 15-08-2016 at 08:36 AM.



  2. #2
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    Re: m=V/v

    What has the potental energy of gasoline got to do with the airflow in a duct?
    Brian - Newton Abbot, Devon, UK
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    Re: m=V/v

    Hi Brian_UK,

    Sorry should have said the word gasoline is a mistake in the question, it should be air

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    Re: m=V/v

    Okay, panic over,
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    Re: m=V/v

    Any knowledge of it Brian_UK?

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    Re: m=V/v

    To be honest, no.

    All that says to me is that it depends on the air density to calculate mass, which we knew anyway.

    Volume flow rate divided by velocity gives the duct/pipe area.

    Sorry I can't be of more help.
    Brian - Newton Abbot, Devon, UK
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    Re: m=V/v

    no problem Brian_UK. I will share what else I know in case anyone has a thought.

    The only other info that may be relevant that I have is,

    P pressure is energy per unit volume in J/m^3
    Pv pressure*velocity is energy per unit mass in J/kg

    So then the thought is energy per unit mass E/m = Pv
    E/m = (E/V) * v
    Take reciprocal of both sides
    m/E = V * 1/E * 1/v
    Multiply both sides by E
    m = V/v

    But Im not sure thats correct.

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    Re: m=V/v

    Does this throw any light on it ?

    https://www.google.co.uk/url?sa=t&so...X8XTmxY8f4nr7A

    Or is the second 'v' standing for specific volume?
    Last edited by Brian_UK; 15-08-2016 at 08:35 PM.
    Brian - Newton Abbot, Devon, UK
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    Re: m=V/v

    That would be it, specific volume. Why the hell I thought velocity. Thanks Brian.

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    Re: m=V/v

    Oh well, got there in the end, at least one of us knows what you were talking about.

    Next time it might be me....
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