Re: [TRNSYS-users] Power Coefficients for Dry Fluid Cooler Type 511

Thank you very much David, that is very clear.

Regards,

Thank you
Metkel Yebiyo BEng (Hons), MSc
CEREB PhD Researcher - Ground Source Heat Pumps
Room T615
Department of Urban Engineering
Faculty of Engineering, Science and the Built Environment
London South Bank University,
103 Borough Road,
London SE1 0AA
Tel: +44 (0)20 7815 7639
E: yebiyom@lsbu.ac.uk

  On Thursday, 2 October 2014, 13:45, David BRADLEY <d.bradley@tess-inc.com> wrote:
  



    Matkel,

      The fan power is computed from an equation of the form:


    pFan = pFan_rtd*(a0 + a1*yFan + a2*yFan^2 + a3*yFan^3 + ... +
    aN*yFan^N)


      where yFan is the fan control signal. If your fan is a simple
    on/off (single speed) device then you want to define a0=0 and a1=1.
    If your fan is a variable speed device and can have a control signal
    anywhere between 0 and 1 then you should set the power coefficients
    as a0=a1=a2=0 and a3=1. This relationship comes from the fan
    affinity laws.

    Kind regards,

     David


On 10/2/2014 05:27, metkell yebiyo
      wrote:

    
Dear
            TRNSYS users,


          
I am simulating a GSHP
            system connected to a 300kW Dry air cooler Type 511.
The Dry air Cooler is
            controlled when the return temperature from the ground
            reaches 30degC, 
then the Dry air cooler
            comes on, to maintain the fluid temperature going to the
            ground to 22degC.


          
My question is, I am
            trying to obtain the amount of power drawn by the fan when
            the Dry air Cooler is operating. But in order for TRNSYS, to
            calculate the power drawn, you need to put the power
            coefficients a1, a2 and a3, how would I obtain this values?
            Is it a matter of calling the Dry air cooler manufacturer
            and ask them for this power coefficients or what do I need
            to do please?


        


        


        
Thank
          you
Metkel
            Yebiyo BEng (Hons), MSc
CEREB PhD
            Researcher - Ground Source Heat Pumps 
Room T615
            
Department
            of Urban Engineering 
Faculty
            of Engineering, Science and the Built Environment
London
            South Bank University, 
103
            Borough Road,
London
            SE1 0AA
Tel: +44
            (0)20 7815 7639
E: yebiyom@lsbu.ac.uk

        
  


          


        


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