<html>
<body>
Dear Pietro,<br>
There are any number of reasons that you could be getting non
convergence errors in your simulation. It sounds as though there are two
problems. One is that there are problems in calculating the solar
radiation on various surfaces based on the data files that you are using.
To track down those errors, please check your parameters and connections
with whatever combination of weather data reading / radiation processing
components you are using. If you are using a combination of Type89 and
16, I would first check to make sure that the Type16 parameter: Starting
day of simulation is correct.<br><br>
The second problem seems to be trouble converging on a solution
for the loop in your simulation that includes unit numbers 40, 24, 23,
25, 41, 27, and 52. Solving the radiation problem may help with this non
convergence but I have my doubts. What you need to do is first try
reducing your time step. Bear in mind that you can only make a control
decision (using Type2 or Type22) once per time step. Next, if you are
dealing with a fluid loop, make sure that you have enough thermal
capacitance in this loop. You should make sure that there is a pipe in
the loop that is large enough to store at least one time step of fluid.
If there is a storage tank in the loop, you usually do not need to add a
pipe. <br><br>
Kind regards,<br>
David<br><br>
At 04:03 AM 6/30/2005, pietro finocchiaro wrote:<br>
<blockquote type=cite class=cite cite=""><font face="arial" size=2>Dear
TRNSYS users,<br>
<br>
I made a project of a solar cooling system and it seems to correctly run
during a yearly simulation, but in the list file appear a lot of warnings
like the following:<br>
<br>
<i>TRNSYS Message 441 : The inputs to the listed units
have not converged at this timestep. The values at the last iteration
will be used and the simulation will proceed.<br>
</font><font face="Times New Roman, Times"> Reported
information : UNITS: 40 24 23 25 41
27 52<br>
</i></font><br>
<font face="Times New Roman, Times">If I modify the simulation start and
stop time in order to a have a shorter period of time, the simulation
give a enormous but different numbers of warnings and the following
error:<br>
</font><br>
<font face="Times New Roman, Times"><i>*** Warning at
time :
4144.000000<br>
</i></font><br>
<font face="Times New Roman, Times"><i> Generated by
Unit : 45<br>
</i></font><br>
<font face="Times New Roman, Times"><i> Generated by
Type : 16<br>
</i></font><br>
<font face="Times New Roman, Times"><i> TRNSYS
Message 437 : The total radiation calculated for one of
the surfaces has exceeded the solar constant. The component solar
quantities (beam and diffuse) have been adjusted such that the sum is
equal to the solar constant<br>
</i></font><br>
<font face="Times New Roman, Times"><i> Reported
information : Sloped Surface Radiation Error<br>
</i></font><br>
<font face="Times New Roman, Times"><i> <br>
</i></font><br>
<font face="Times New Roman, Times"><i>*** Fatal Error at
time : 4144.000000<br>
</i></font><br>
<font face="Times New Roman, Times"><i> Generated by
Unit : Not applicable or not available<br>
</i></font><br>
<font face="Times New Roman, Times"><i> Generated by
Type : Not applicable or not available<br>
</i></font><br>
<font face="Times New Roman, Times"><i> TRNSYS
Message 450 : The maximum number of warnings allowed
per simulation has been exceeded. Please fix these warnings or increase
the limit on the number of warnings allowed per simulation (LIMITS
command)<br>
</i></font><br>
<font face="Times New Roman, Times"><i> Reported
information : Not available<br>
</i></font><br>
<font face="Times New Roman, Times"> <br>
</font><br>
<font face="Times New Roman, Times">I’m not able to locate the problem. I
think it has no sense to increase the maximum number of warnings allowed
per simulation..<br>
</font><br>
<font face="Times New Roman, Times">Thanks to all,<br>
</font><br>
<font face="arial"> <br>
</font><br>
<font face="arial">
--------------------------------------------------------------</font>
<br>
Pietro Finocchiaro <br>
Dipartimento di Ricerche Energetiche ed Ambientali <br>
Università di Palermo <br>
Tel: +39 (0)91 236277 <br>
E-mail:<font color="#0000FF">
</font><a href="mailto:finocchiaro@dream.unipa.it">
finocchiaro@dream.unipa.it</a> <br>
<font face="arial"> </font> <br>
<font face="arial"> </font> <br>
<font face="Times New Roman, Times"> <br>
</font>_______________________________________________<br>
TRNSYS-users mailing list<br>
TRNSYS-users@engr.wisc.edu<br>
<a href="https://www.cae.wisc.edu/mailman/listinfo/trnsys-users" eudora="autourl">
https://www.cae.wisc.edu/mailman/listinfo/trnsys-users</a></blockquote>
<x-sigsep><p></x-sigsep>
****************************************************************************************<br>
Thermal Energy System Specialists (TESS), LLC <br>
David
BRADLEY
2916 Marketplace Drive - Suite 104 <br>
Partner
Madison, WI 53719 <br>
Phone: (608) 274-2577 USA <br>
Fax: (608) 278-1475 <br>
E-mail: bradley@tess-inc.com <br>
Web Pages:
<a href="http://www.tess-inc.com/" eudora="autourl">
http://www.tess-inc.com</a>
and
<a href="http://www.trnsys.com/" eudora="autourl">
http://www.trnsys.com<br><br>
</a>"Providing software solutions for today's energy engineering
projects" <br>
****************************************************************************************<br>
</body>
</html>