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  1. #1
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    temperature gradient



    Gents,

    Are you aware of any standard calculation rules, industry standards or codes, that allow to consider temperature gradient / stratification in elevation?

    Thanks in advance
    rooibos



  2. #2
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    Re: temperature gradient

    Quote Originally Posted by rooibos View Post
    Gents,

    Are you aware of any standard calculation rules, industry standards or codes, that allow to consider temperature gradient / stratification in elevation?

    Thanks in advance
    rooibos
    Hi rooiboos, With you being in heaven I thought you would know this, anyway this might be what you are looking for.

    http://en.wikipedia.org/wiki/Lapse_r...cal_definition

    regards Norm
    My wife used to say you never listen to a word I say at least I think that what she said

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    Re: temperature gradient

    I think 'heaven' is somewhere in The Netherlands or Belgium.
    If you want standards, then we have to know standard for which country.
    I don't think there's an standard for heaven.
    I there something wrong with providing us the right place you live?
    It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.

  4. #4
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    Re: temperature gradient

    Gents,

    My apologize, I did not express correctly.
    The problem is that there is a room - 6.5m x 3m x 3.5m height, 3m (WxLxH) and equipment with extremely high heat dissipations.
    Everybody knows that "the hot air goes up and cold air stays down" and I would like to use this fundamental rule to optimize the heat load calculations.

    I hope this time is a bit more clear.

    Regards,
    rooibos

    P.S.

    Heaven is The Netherlands in case.

  5. #5
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    Re: temperature gradient

    Quote Originally Posted by rooibos View Post
    Gents,

    My apologize, I did not express correctly.
    The problem is that there is a room - 6.5m x 3m x 3.5m height, 3m (WxLxH) and equipment with extremely high heat dissipations.
    Everybody knows that "the hot air goes up and cold air stays down" and I would like to use this fundamental rule to optimize the heat load calculations.

    I hope this time is a bit more clear.

    Regards,
    rooibos

    P.S.

    Heaven is The Netherlands in case.

    HI I now know where Heaven is thank you, first of all what are you trying to achieve ie what product are you trying to cool and presuming you know heat load calculations it should be quite easy,or is that what you are trying to find. we need more information in order to help you

    Norm
    Last edited by Brian_UK; 16-12-2009 at 07:17 PM. Reason: Closed quote bracket ]
    My wife used to say you never listen to a word I say at least I think that what she said

  6. #6
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    Re: temperature gradient

    Yes heat rises but cold air does not stay down.

    It is drawn towards the hot air by convection and will slowly heat up towards the temperature of the hot air.

    The heat load calculation should surely be based on the heat load itself and not the fact that the heat will rise.
    Brian - Newton Abbot, Devon, UK
    Retired March 2015

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    Re: temperature gradient

    Yes, I know that the heat load calculation is something simple, and they are based on the heat dissipations, but also the temperature is not the same at 1m and at 6m.
    Actually the height is 6.5m. the area is 10,5m2.

    I was wondering if I could reduce the cooling coil capacity.
    The heat load is 120 kW, and outside design temperature is 40 degC. and 75% RH; Inside - 30 degC and 50%RH.

    Of course the air distribution is organized as displacement ventilation.

    regards,
    rooibos

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    Re: temperature gradient

    What is the maximum air movement velocity within the room with your beloved air displacement system ?

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    Re: temperature gradient

    Quote Originally Posted by Thermatech View Post
    What is the maximum air movement velocity within the room with your beloved air displacement system ?
    About 0.75 m/s. And?

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    Re: temperature gradient

    This air movement max velocity excludes just about every type of mass produced air conditioning product split systems or most types of fan coil unit.

    This is a clever ploy to restrict free trade into your country. As almost all packaged mass produced air conditioning products cannot meet this specification.

    Only a locally designed & specially manufactured air displacment system can meet such a low air velocity specification.

    Mass produced air conditioning products which are sold freely throughout the world are effectively banned from sale in your country while manufacturers in your country are free to export any air conditioning product.

    This is nothing less than market protectionism.

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