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Matkel,<br>
The fan power is computed from an equation of the form:<br>
<br>
pFan = pFan_rtd*(a0 + a1*yFan + a2*yFan^2 + a3*yFan^3 + ... +
aN*yFan^N)<br>
<br>
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.<br>
Kind regards,<br>
David<br>
<br>
<br>
<div class="moz-cite-prefix">On 10/2/2014 05:27, metkell yebiyo
wrote:<br>
</div>
<blockquote
cite="mid:1412245625.11082.YahooMailNeo@web173103.mail.ir2.yahoo.com"
type="cite">
<div style="color:#000; background-color:#fff; font-family:Courier
New, courier, monaco, monospace, sans-serif;font-size:10px">
<div class="" style=""><span style="font-size: 13px;" class="">Dear
TRNSYS users,</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class=""><br class="" style="">
</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class="">I am simulating a GSHP
system connected to a 300kW Dry air cooler Type 511.</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class="">The Dry air Cooler is
controlled when the return temperature from the ground
reaches 30degC, </span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class="">then the Dry air cooler
comes on, to maintain the fluid temperature going to the
ground to 22degC.</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class=""><br class="" style="">
</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class="">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?</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><br
class="" style="">
</div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><br
class="" style="">
</div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><br
class="" style="">
</div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class="">Thank
you</div>
<div class="" style=""><span style="font-size: 13px;">Metkel
Yebiyo BEng (Hons), MSc<o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">CEREB PhD
Researcher - Ground Source Heat Pumps <o:p class=""
style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">Room T615
<o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">Department
of Urban Engineering <o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">Faculty
of Engineering, Science and the Built Environment<o:p
class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">London
South Bank University, <o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">103
Borough Road,<o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">London
SE1 0AA<o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">Tel: +44
(0)20 7815 7639<o:p class="" style=""></o:p></span></div>
<div class="" style=""><span style="font-size: small;">E: <a
moz-do-not-send="true" href="mailto:yebiyom@lsbu.ac.uk"
class="" style="">yebiyom@lsbu.ac.uk</a><o:p class=""
style=""></o:p></span></div>
<div style="background-color: transparent;" class="">
</div>
<div class="" style=""><o:p class="" style="font-size: small;"> </o:p></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><span
style="font-size: 13px;" class=""><br class="" style="">
</span></div>
<div style="color: rgb(0, 0, 0); font-size: 13px; font-family:
'Courier New', courier, monaco, monospace, sans-serif;
font-style: normal; background-color: transparent;" class=""><br
class="" style="">
</div>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
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</blockquote>
<br>
<pre class="moz-signature" cols="72">--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
Madison, WI 53703 USA
P:+1.608.274.2577
F:+1.608.278.1475
<a class="moz-txt-link-abbreviated" href="mailto:d.bradley@tess-inc.com">d.bradley@tess-inc.com</a>
<a class="moz-txt-link-freetext" href="http://www.tess-inc.com">http://www.tess-inc.com</a>
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