Sub-zero temperatures on upper layer temperature devices

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Patrik Král

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May 13, 2022, 2:55:25 AM5/13/22
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Hi,

Has anyone encountered an issue with devices with upper layer temperature when the results look like this?:

s                   C
Time            SUPPORT_TEMP_01
0                   30.10862
1.807392     -566.3
3.614785     -566.299
5.422177     -566.3
7.224091     -566.301
...
Then it goes to some insanely high numbers, then suddenly back to sub-zero. Even the initial temperature is off - it should be 20 °C. The upper layer temperature on trigger is really odd - 614061 °C, 18578.3 °C,.... While HHR and everything else seems correct. Even the temperature slice file shows the correct temperatures and clearly shows that the zone temp devices trigger too early with totally unrealistic temperatures.

Using "CHECK_HT=.TRUE." doesn't help, but I think LES intead of VLES did help in some simulation (but is slower, of course).

Code lines example:
&HEAD CHID='EXAMPLE'/
&TIME T_END=1800.0/
&DUMP DT_RESTART=50.0, DT_SL3D=0.25/
&MISC HUMIDITY=50.0, CHECK_HT=.TRUE./
&PRES MAX_PRESSURE_ITERATIONS=200/
...
&DEVC ID='ADMIN_WINDOW_WEST_01', QUANTITY='UPPER TEMPERATURE', XB=25.1,25.1,16.5,16.5,0.0,2.9, SETPOINT=500.0/

FDS version:
 Current Date     : May 13, 2022  16:47:54
 Revision         : FDS6.7.7-1109-g60d1a65d0-master
 Revision Date    : Tue May 10 15:32:45 2022 -0400
 Compiler         : Intel ifort 2021.2.0
 Compilation Date : 12/05/2022  00:31


Does anybody know what might be wrong (with VLES)?
Thanks a lot.


Best regards

Patrik
EXAMPLE_devc.csv
EXAMPLE_devc_ctrl_log.csv

Patrik Král

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May 13, 2022, 3:08:45 AM5/13/22
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Correction,
LES solver has the same issue as VLES.

Dne pátek 13. května 2022 v 18:55:25 UTC+12 uživatel Patrik Král napsal:

Patrik Král

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May 13, 2022, 3:18:21 AM5/13/22
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Using the release version of FDS and its mpiexec doesn't change a thing.

 Current Date     : May 13, 2022  19:15:32
 Revision         : FDS6.7.7-0-gfe0d4ef38-release
 Revision Date    : Thu Nov 18 17:10:22 2021 -0500
 Compiler         : Intel ifort 2021.4.0
 Compilation Date : Fri 11/19/2021  08:57 AM

Dne pátek 13. května 2022 v 19:08:45 UTC+12 uživatel Patrik Král napsal:

dr_jfloyd

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May 13, 2022, 7:23:43 AM5/13/22
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Please post a simple input file that demonstrates this problem to the Issue Tracker (https://github.com/firemodels/fds/issues)

Patrik Král

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May 13, 2022, 8:09:13 AM5/13/22
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Done, here:

Thank you for looking into it.

Dne pátek 13. května 2022 v 23:23:43 UTC+12 uživatel dr_jfloyd napsal:
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