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Dear Lorenzo, <br>
We addressed some problems with Type60's heat exchanger UA
calculation in TRNSYS 16. However, in TRNSYS 15, you might have some luck
by changing the Type60 internal time step parameter (parameter 28)<br>
Kind regards,<br>
David<br><br>
<br>
At 10:33 3/13/2006, Lorenzo Zamboni wrote:<br>
<blockquote type=cite class=cite cite="">
<font face="Times New Roman, Times" size=4 color="#666666">Dear all,<br>
I am a TRNSYS 15 user and I am facing problems with
type 60 used to simulate a tank with 1 internal heat exchanger.<br>
Simulation seems to go on without problems but into
the list file a warning message is sent by the type 60 when trying to
solve the heat exchanger internal heat transfer coefficient (UAhx)
like the following:<br>
%%% TYPE60 WARNING: UAhx UNABLE TO<br>
CONVERGE IN 500 ITERATIONS AT TIME=<br>
8.000000
500 %%%<br><br>
I tried to change the number of nodes, the size of the
heat exchanger and/or tank but that warning still continues to appear
almost for all the timesteps (I am using 1/4-hour simulation timestep). I
do not think I can trust those calculations while these warnings
exists.<br>
Please, let me know if someone knows some possible
solution\explanation.<br>
<br>
Thank you,<br>
Lorenzo</font><font color="#666666"> <br>
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