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Dear trnsys users,<br><br>
I'm having a lot of problems with a simulation with an active layer
(modelling a sort of capillary system, having many small pipes in
parallel;<br>
the panel is split into 4 parts by the autosegmentation in PreBid):
<ul>
<li>at some time steps the fluid outlet temperature of the active layer
(ouput 58) oscillates without any physical meaning;
<li>at these time steps there is a large difference between the energy
input by fluid to zone obtained as Qalfl (output 59) and calculated as
m.c.DT;
<li>the energy balance of the surface containing the active layer (output
906) is never zero, even when water is not flowing into the panel.
</ul>The oscilllations are more likely to occurr if the radiant system is
switched on/off.<br>
Changing the simulation time step from a few minutes to 1 h has no
effect.<br>
Convergence and integration relative tolerances are set to 0.001.<br>
No convergence problem is reported in the list file.<br><br>
I wonder if anybody encountered such problems with active layers
simulation.<br>
Any suggestion will be useful, since I really don't know how to go on
!<br><br>
Many thanks in advance<br><br>
Adriana<br><br>
<br><br>
<br><br>
----------------------------------------------------------------------------------------------------------<br>
Adriana Angelotti, PhD<br>
Politecnico di Milano<br>
Dipartimento di Scienza e Tecnologie dell'Ambiente Costruito (Best)<br>
v. Bonardi 3<br>
20133 Milano<br>
Italy<br>
Ph +39 02.2399.5183<br>
Fax +39 02.2399.5118<br>
e-mail adriana.angelotti@polimi.it<br>
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