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<p>No - there is no way in the current TRNSYS library to model the collector or pipes to model the drainback situation where air replaces water. That being said, you could create a simulation where the water in the collector and pipes is "thrown away" when the pump starts up each morning until enough time has passed where water would again be filling the system. In that way you wouldn't be penalized for the thermal losses from the fluid to the ambient overnight. While it's not technically perfect, it does replicate to some extent what you are trying to do.</p>
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<p>Jeff</p>
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<p>Jeff Thornton</p>
<p><em>President - TESS LLC</em></p>
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<p>On 10/19/2013 9:35 am, Malak Dakhli wrote:</p>
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<div>Hi, </div>
<div>I am modelling a drainback SDWH with TRNSYS 17 but in such system while it's working there is water in the collectors and when it stops the water drains to the tank and air replaces water in the collectors. </div>
<div>My question; is there a way how to define these two fluids in the collectors?</div>
<div>Best regards</div>
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<blockquote style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-color: #cccccc; border-left-style: solid; padding-left: 1ex;"><strong><span style="font-size: 11pt; font-family: Calibri,sans-serif; color: #e4a600;">Malak Dakhli, ing., M.Sc. </span></strong><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #404040;">Chercheuse / <em>Researcher<br /></em></span><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #262626;">Chaire de recherche industrielle en technologies de l'énergie et en efficacité énergétique (T3E) /<br /></span><em><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #262626;">Industrial research chair in technologies of energy and energy efficiency (T3E)<br /></span></em><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #404040;">École de technologie supérieure,1100 Notre-Dame Ouest, Montreal, Qc, Canada, H3C 1K3<br /></span><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #404040;"><a style="color: #1155cc;">+1 514 559-3889</a> | </span><span style="font-size: 11pt; font-family: Calibri,sans-serif; color: #1f497d;"><a style="color: #1155cc;" href="mailto:mostafa@t3e.info"><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #e4a600;">malak.dakhli@gmail.com</span></a></span><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #e4a600;"> </span><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #404040;">| </span><span style="font-size: 11pt; font-family: Calibri,sans-serif; color: #1f497d;"><a style="color: #1155cc;" href="mailto:mostafa@t3e.info"><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #e4a600;">malak@t3e.info</span></a></span><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #e4a600;"> </span><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #404040;">| </span><span style="font-size: 11pt; font-family: Calibri,sans-serif; color: #1f497d;"><a style="color: #1155cc;" href="http://www.t3e.info/"><span style="font-size: 8pt; font-family: Arial,sans-serif; color: #e4a600;">www.t3e.info</span></a></span></blockquote>
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<div><strong style="font-size: 16px;">La Ville de Lévis, la Conférence Régionale des Élus de Chaudière-Appalaches, Énergie Valero Inc. et Ecosystem, partenaires et piliers de t3e : merci</strong><em style="color: #000099;"><br /></em></div>
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