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Matteo,<br>
You need to use a smaller timestep; something on the order of 5 to 15
minutes would be appropriate. I'm actually somewhat surprised that the
simulation runs at all - the data file has hourly values in it and with
a two hour timestep, it would have to skip every other point in the
data file. I didn't think Type15 could do that. I would also recommend
that you put some pipes between the tank and solar collector. You need
to make sure that the total volume of liquid that the pump can transfer
in the space of one timestep is smaller than the volume of the loop
itself. The pump and solar collector models neglect the volume of
liquid that they contain. I believe that the Type60 internal heat
exchanger calculates the liquid volume. However that volume may be
smaller than the pumps rated flow rate times the timestep which, from a
simulation point of view, means that the liquid would make more than
one complete circuit within the space of one timestep. That can cause
numerical instability in your simulation.<br>
Kind regards,<br>
David<br>
<br>
<br>
Matteo DF wrote:
<blockquote
cite="mid:bdcf22dd0908110655l7d83b261u7281d828f7b449e9@mail.gmail.com"
type="cite">Hi,<br>
I'm trying to simulate a small project with a solar collector, a pump
and a storage tank. I used 12 m^2 of panels which flow goes directly to
the heat exchanger of the tank... The circulation pump provides the
correct flow.<br>
I have some difficulties as I get some convergence warnings (warning
441) The convergence error is between the solar unit and the tank one.<br>
<br>
I attach my little project. Can you tell me were I'm going wrong?<br>
<br>
Many Thanks.<br>
Matteo.<br clear="all">
<br>
-- <br>
La scoperta è vedere ciò che tutti hanno sempre visto e<br>
pensare ciò che nessuno ha mai pensato.<br>
(Albert Szent-Gyorgyi, scopritore della vitamina C e premio Nobel)<br>
<br>
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