<html>
<head>
<meta content="text/html; charset=windows-1252"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<span style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;" lang="EN-US">Alaia,<br>
Type534 results have been matched against experimental data on
numerous occasions. If you add heat to the top of a tank by a
miscellaneous energy flow then there is no physical flow of water
through the tank that will cause the top node to get hotter and
hotter. The nodes below will heat up by conduction somewhat but
there is no other mechanism either in the model or in reality that
will cause the entire tank to heat up if you are only adding
energy to the top node.<br>
There are a number of parameters that you can use to either
enhance or decrease stratification if the temperature profiles you
are seeing in the tank do not match the reality of your
experimental data. Type534 does not directly account for
convection cells that form in a tank if heat is added to the
bottom nodes (note that the top of the tank is node 1). Such cells
need to be accounted for using the inversion mixing flow rate. An
inversion is defined as a situation where a node nearer the bottom
of the tank has a higher temperature than a node above. <br>
regards,<br>
David<br>
<br>
</span><br>
<div class="moz-cite-prefix">On 07/02/2015 01:55, Alaia Sola wrote:<br>
</div>
<blockquote cite="mid:DUB113-W130956A711D0E6058A8432FE5970@phx.gbl"
type="cite">
<style><!--
.hmmessage P
{
margin:0px;
padding:0px
}
body.hmmessage
{
font-size: 12pt;
font-family:Calibri
}
--></style>
<div dir="ltr">
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">Hi everyone,<o:p></o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">I am using
Type534 with Plug-in, inserting 1 port and 1 miscellaneous
heat flow to it. My
doubt is about temperature stratification in the tank. Even
if I increase the
number of nodes, the temperature difference between the node
where I insert the
heat flow and the rest of the nodes is too large, i.e. the
nodes without external heating barely warm up. </span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">It also happens even if I remove the port
and, consequently, simulate it as a tank without any inlet
or outlet: the lower
nodes barely increase their temperature (I want the
miscellaneous heat flow in
node 1 or 2), no matter the time length I run the
simulation... The upper nodes
do reach the desired temperature (I have a controller to the
heater that is connected
to miscellaneous heat flow for that) but the lower nodes
remain almost at
constant temperature. I tried to change the “inversion
mixing flow rate” to
both high and low values, negative and positive values,
zero… but the changes
in T of the nodes are not visible. I want to increase T of
water in tank from
20ºC to 150ºC and I have a quite high water draw from the
tank, thus I don’t want
that only one or two nodes reach 150ºC, but I want most or
all of the tank to do so instead… no
matter how much time it takes to heat it up. </span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">How to make the lower nodes to heat up? </span><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">Which other
parameter can I change so the stratification in the tank
really works? Is there
any other parameter to change rather than “inversion mixing
flow rate” to get
normal stratification? Should I use another type?<o:p></o:p></span><font
face="Times New Roman">
</font></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">Thank you very
much in advance.<o:p></o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US"><o:p> </o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">Alaia Sola Saura<o:p></o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">Project engineer<o:p></o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US">Thermal Energy
and Building Performance Group<o:p></o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: EN-US; mso-fareast-language: ES;"
lang="EN-US"><o:p> </o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><b><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-fareast-language: ES;">IREC</span></b><b><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-ansi-language: ES-TRAD; mso-fareast-language: ES;"
lang="ES-TRAD"><o:p></o:p></span></b></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><b><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-fareast-language: ES;">Institut de Recerca en Energia
de
Catalunya<o:p></o:p></span></b></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="color: rgb(31, 73, 125); font-family:
"Arial","sans-serif"; font-size: 10pt;
mso-fareast-language: ES;"><a moz-do-not-send="true"
href="http://www.irec.cat"><font color="#0000ff">www.irec.cat</font></a><o:p></o:p></span></p>
<font face="Times New Roman">
</font>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="mso-ansi-language: EN-US;" lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="mso-ansi-language: EN-US;" lang="EN-US"><o:p></o:p></span> </p>
<font face="Times New Roman">
</font> </div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
TRNSYS-users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:TRNSYS-users@lists.onebuilding.org">TRNSYS-users@lists.onebuilding.org</a>
<a class="moz-txt-link-freetext" href="http://lists.onebuilding.org/listinfo.cgi/trnsys-users-onebuilding.org">http://lists.onebuilding.org/listinfo.cgi/trnsys-users-onebuilding.org</a>
</pre>
</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>
<a class="moz-txt-link-freetext" href="http://www.trnsys.com">http://www.trnsys.com</a></pre>
</body>
</html>