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<p>Pouyan,</p>
<p> The method I usually use when sizing equipment (radiators or
otherwise) is to set each room of the building up with a set point
temperature and an automatic heating type in TRNBuild. I then find
the max hourly heating required from among the Type56 outputs and
then size each piece of equipment accordingly. It sounds as though
your method is the same.</p>
<p> 10C sounds correct for a design air temperature but keep in mind
that the radiator's capacity can be quite different if you are
asking it to maintain an air temperature that is significantly
different than the design air temperature. You may run into
trouble if you set the design air temperature to 10C but are in
fact trying to maintain 20C in the room.</p>
<p> I unfortunately don't have any experience regarding setting the
number of channels. However, I would encourage you to play around
with the value. Make your best guess and run a simulation.
Increase the number by 20% and run again. Decrease it by 20% and
run it again. Look at the results each time and determine whether
those results are sensitive to the value in question. If they are
then you can dig in and try and get a more accurate value; perhaps
by talking to manufacturers. If they aren't then you can proceed
using your best guess value.</p>
<p>kind regards,</p>
<p> David</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 07/14/2021 08:15, Pouyan
Talebizadehsardari (Staff) via TRNSYS-users wrote:<br>
</div>
<blockquote type="cite"
cite="mid:LO0P265MB48959D1E5A01E3816B8D8E8FCD139@LO0P265MB4895.GBRP265.PROD.OUTLOOK.COM">
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<p class="MsoNormal"><span style="font-size:12.0pt">Dear All,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">I hope all
are well. I’d really appreciate it if anyone can help me
with the following questions:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">I am using a
radiator (Type 1231) for each room to warm up a building
(Type 56). First, I determined the maximum loss for this
building by choosing a heating setpoint. Then, I chose the
maximum heat loss for each room as the design capacity of
the radiator. Does anyone know if I do it correct?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">I chose 55C
for the design surface temperature of the radiator. My
boiler works at the temperature of 60C. What about the
design air temperature? As I know, these values are selected
based on the manufacturer and it is usually 50C less than
the mean temperature of the radiator. So, I consider it the
predefined value of 10C. Am I correct?
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Also, for
the number of pipes, as I understand, it is related to
correct the heat transfer to the room and a higher number of
pipes results in a lower heat transferred to the room. Does
anyone know if it is exactly equal to the number of water
channels insider the radiator? If yes, so, It should be
related to the length of the radiator and so a higher number
should be selected for a radiator with a higher capacity.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Thanks in
advance<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Kind regards<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Pouyan<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="background:white"><b><span
style="color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">*******************************************************************************</span></b><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#222222;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><b><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">Pouyan
Talebizadeh Sardari</span></b><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">, BSc MSc PhD
AFHEA</span><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#222222;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">Centre for
Sustainable Energy Use in Food Chains,
<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">Institute of
Energy Futures,
<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">Brunel
University London,
<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">Kingston Lane,
Uxbridge, Middlesex, UB8 3PH, UK
</span><span style="font-size:12.0pt;font-family:"Times
New
Roman",serif;color:#222222;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#201F1E;border:none windowtext
1.0pt;padding:0cm;mso-fareast-language:EN-GB">Email: </span><span
style="mso-fareast-language:EN-GB"><a
href="mailto:pouyan.talebizadehsardari@brunel.ac.uk"
moz-do-not-send="true"><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:blue;border:none windowtext
1.0pt;padding:0cm">pouyan.talebizadehsardari@brunel.ac.uk</span></a></span><span
style="font-size:12.0pt;font-family:"Times New
Roman",serif;color:#222222;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<pre class="moz-signature" cols="72">--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
3 North Pinckney Street - suite 202
Madison, WI 53703 USA
P:+1.608.274.2577
<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>
<a class="moz-txt-link-freetext" href="http://www.trnsys.com">http://www.trnsys.com</a></pre>
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