<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:16px"><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style=""><span id="yiv8405734802yui_3_16_0_1_1426671778124_9353" class="" style="">Dear Leen</span></div><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style=""><br clear="none" class="" style=""></div><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style="">Please attached the simulation output for 8760 hours for Casablanca weather. I didn't find any problem with the simulation.</div><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style=""><br clear="none" class="" style=""></div><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style="">Regards</div><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style=""><br clear="none" class="" style=""></div><div dir="ltr" id="yiv8405734802yui_3_16_0_1_1426671778124_9095" class="" style="">Nidal Abdalla</div><br> <div style="font-family: times new roman, new york, times, serif; font-size: 16px;" id="yui_3_16_0_1_1426678896648_5902"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1426678896648_5901"> <div dir="ltr" id="yui_3_16_0_1_1426678896648_5924"> <hr size="1" id="yui_3_16_0_1_1426678896648_5925"> <font size="2" face="Arial" id="yui_3_16_0_1_1426678896648_5923"> <b><span style="font-weight:bold;">From:</span></b> leen peeters <l.f.r.peeters@gmail.com><br> <b><span style="font-weight: bold;">To:</span></b> TRNSYS users mailing list at OneBuilding.org <trnsys-users@lists.onebuilding.org> <br> <b><span style="font-weight: bold;">Sent:</span></b> Tuesday, March 17, 2015 7:20 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [TRNSYS-users] active layer<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1426678896648_5900"><br><div id="yiv7021176783"><div id="yui_3_16_0_1_1426678896648_5899"><div dir="ltr" id="yui_3_16_0_1_1426678896648_5943">Marion,<div id="yui_3_16_0_1_1426678896648_5944"><br clear="none"></div><div id="yui_3_16_0_1_1426678896648_5945">yes indeed. This is a kind of solar thermal system. This is the way it is now installed on several roofs. So, the input values are correct.</div><div id="yui_3_16_0_1_1426678896648_5946"><br clear="none"></div><div id="yui_3_16_0_1_1426678896648_5947">Leen</div></div><div class="yiv7021176783gmail_extra" id="yui_3_16_0_1_1426678896648_5898"><br clear="none"><div class="yiv7021176783gmail_quote" id="yui_3_16_0_1_1426678896648_5949">On Tue, Mar 17, 2015 at 3:12 PM, hotline <span dir="ltr" id="yui_3_16_0_1_1426678896648_5948"><<a rel="nofollow" shape="rect" ymailto="mailto:hotline@transsolar.com" target="_blank" href="mailto:hotline@transsolar.com">hotline@transsolar.com</a>></span> wrote:<br clear="none"><blockquote class="yiv7021176783gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;" id="yui_3_16_0_1_1426678896648_6024">
<div class="qtdSeparateBR"><br><br></div><div class="yiv7021176783yqt5107658097" id="yiv7021176783yqt76777"><div lang="DE" id="yui_3_16_0_1_1426678896648_6023">
<div id="yui_3_16_0_1_1426678896648_6022">
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6021"><span style="font-size:11.0pt;">Leen,<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal"><span style="font-size:11.0pt;"><u></u> <u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">before I start looking deeper into this one question concerning the “active layer design”.<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"><u></u> <u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">The pipes of your active layer have an outside diameter of 2 cm and the pipe spacing (center to center)<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6025"><span lang="EN-US" style="font-size:11.0pt;">is only 5 cm. This is very dense. If you subtract half the outside diameter this means that you have 3 cm material in between only!<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">Also, the coverage above/below is very small. The adjacent layer thickness is 0. 15. If you subtract half the<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6042"><span lang="EN-US" style="font-size:11.0pt;" id="yui_3_16_0_1_1426678896648_6094">outside diameter there is only 5 mm coverage. This really low!<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"><u></u> <u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">Are you sure that this is the system you like to simulate?<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"><u></u> <u></u></span></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">Marion<u></u><u></u></span></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6095"><span lang="EN-US" style="font-size:11.0pt;"><u></u> <u></u></span></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6026"><b><span style="font-size:10.0pt;">Von:</span></b><span style="font-size:10.0pt;"> TRNSYS-users [mailto:<a rel="nofollow" shape="rect" ymailto="mailto:trnsys-users-bounces@lists.onebuilding.org" target="_blank" href="mailto:trnsys-users-bounces@lists.onebuilding.org">trnsys-users-bounces@lists.onebuilding.org</a>]
<b>Im Auftrag von </b>leen peeters<br clear="none">
<b>Gesendet:</b> Dienstag, 17. März 2015 08:52<br clear="none">
<b>An:</b> TRNSYS users mailing list at OneBuilding.org<br clear="none">
<b>Betreff:</b> Re: [TRNSYS-users] active layer<u></u><u></u></span></div><div id="yui_3_16_0_1_1426678896648_6033"><div class="yiv7021176783h5" id="yui_3_16_0_1_1426678896648_6032">
<div class="yiv7021176783MsoNormal"><u></u> <u></u></div>
<div id="yui_3_16_0_1_1426678896648_6097">
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6096">Marion,<u></u><u></u></div>
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<div class="yiv7021176783MsoNormal"><u></u> <u></u></div>
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<div class="yiv7021176783MsoNormal">sorry it took me some time, but I was mostly offline last week.<u></u><u></u></div>
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<div class="yiv7021176783MsoNormal">The model is in attach. I simulated with the weather file of Casablanca.<u></u><u></u></div>
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<div class="yiv7021176783MsoNormal"><u></u> <u></u></div>
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<div>
<div class="yiv7021176783MsoNormal">Thanks already for your input!<u></u><u></u></div>
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<div class="yiv7021176783MsoNormal"><u></u> <u></u></div>
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<div>
<div class="yiv7021176783MsoNormal">Leen<u></u><u></u></div>
</div>
</div>
<div id="yui_3_16_0_1_1426678896648_6031">
<div class="yiv7021176783MsoNormal"><u></u> <u></u></div>
<div id="yui_3_16_0_1_1426678896648_6030">
<div class="yiv7021176783MsoNormal">On Thu, Mar 5, 2015 at 1:59 PM, Marion Hiller <<a rel="nofollow" shape="rect" ymailto="mailto:Hiller@transsolar.com" target="_blank" href="mailto:Hiller@transsolar.com">Hiller@transsolar.com</a>> wrote:<u></u><u></u></div>
<div id="yui_3_16_0_1_1426678896648_6029">
<div id="yui_3_16_0_1_1426678896648_6028">
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">Dear Leen,</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6098"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">The minimum mass flow rate is checked in order to assure the validity of the linear
approximation</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">of the e-function between inlet and outlet temperature. In the attached figure</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">you see that the deviation between linear approach and the e-function is to large</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">(Read line). If you split the tab into two segments in series the linear approach is
used </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">for each segment and it matches well the e-funtion (see the two green lines).</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">A smaller time step doesn’t help for this problem, that’s correct.</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">In general, the min. mass flow rate is checked in TRNbuild prior the simulation.</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">The calculated min. mass flow rate during the simulation might differ from the one in
TRNbuild,</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">because Type56 differentiates between a laminar and turbulent flow, respectively.</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">(TRNBuild doesn’t.)</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">Without knowing the simulation files it is hard to tell what might go wrong with your
simulation. </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">It sounds strange to me that the last segment is causing the error as well as the large
difference between</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">12 kg/h m² and 30 kg/h m².</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">If you can’t find anything, we may have a quick look at the inputs file.(<a rel="nofollow" shape="rect" ymailto="mailto:Hotline@transsolar.com" target="_blank" href="mailto:Hotline@transsolar.com">Hotline@transsolar.com</a>)</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6027"><span lang="EN-US" style="font-size:11.0pt;">Best,</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span lang="EN-US" style="font-size:11.0pt;">Marion</span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6041"><span lang="EN-US" style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><span style="font-size:11.0pt;"> </span><u></u><u></u></div>
<div class="yiv7021176783MsoNormal"><b><span style="font-size:10.0pt;">Von:</span></b><span style="font-size:10.0pt;"> TRNSYS-users [mailto:<a rel="nofollow" shape="rect" ymailto="mailto:trnsys-users-bounces@lists.onebuilding.org" target="_blank" href="mailto:trnsys-users-bounces@lists.onebuilding.org">trnsys-users-bounces@lists.onebuilding.org</a>]
<b>Im Auftrag von </b>leen peeters<br clear="none">
<b>Gesendet:</b> Mittwoch, 4. März 2015 11:24<br clear="none">
<b>An:</b> <a rel="nofollow" shape="rect" ymailto="mailto:trnsys-users@cae.wisc.edu" target="_blank" href="mailto:trnsys-users@cae.wisc.edu">trnsys-users@cae.wisc.edu</a><br clear="none">
<b>Betreff:</b> [TRNSYS-users] active layer</span><u></u><u></u></div>
<div id="yui_3_16_0_1_1426678896648_6103">
<div id="yui_3_16_0_1_1426678896648_6102">
<div class="yiv7021176783MsoNormal"> <u></u><u></u></div>
<div id="yui_3_16_0_1_1426678896648_6101">
<div class="yiv7021176783MsoNormal">Dear all,<u></u><u></u></div>
<div>
<div class="yiv7021176783MsoNormal"> <u></u><u></u></div>
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<div>
<div class="yiv7021176783MsoNormal">we are using the active layer model of EMPA, built in in type 56, to simulate a solar boiler of the type equal to floor heating. In our case we used the auto segmentation leading
to 3 different segments of the active layer. <u></u><u></u></div>
</div>
<div>
<div class="yiv7021176783MsoNormal">With 66 kg/h at 1,055 specific weight, inlet temperatures below 25 DC gave a fluent simulation at 15 minutes timestep. However, once simulating with higher inlet temperatures warmer
climatic zones (e.g. Casablanca) fail at around 3400 hours in the simulation. In this case, we get a specific message that the inlet mass flow rate for the third part of the segmented roof requires a minimum mass flow rate that is higher than the input one.
Opening the TRNBUILD file, the minimum is around 12 kg/h. The message in the list file mentions a minimum of over 30. A smaller timestep did not change the error.<u></u><u></u></div>
</div>
<div>
<div class="yiv7021176783MsoNormal"> <u></u><u></u></div>
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<div class="yiv7021176783MsoNormal">Are we too close to the safety limits built in the EMPA model, or is there another thing we forgot to take into account? <u></u><u></u></div>
</div>
<div id="yui_3_16_0_1_1426678896648_6100">
<div class="yiv7021176783MsoNormal" id="yui_3_16_0_1_1426678896648_6099"> <u></u><u></u></div>
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<div class="yiv7021176783MsoNormal">Thanks already!<u></u><u></u></div>
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<div class="yiv7021176783MsoNormal"> <u></u><u></u></div>
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<div class="yiv7021176783MsoNormal">Leen<u></u><u></u></div>
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</div>
</div>
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<div class="yiv7021176783MsoNormal" style="margin-bottom:12.0pt;"><br clear="none">
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