|
[Sponsors] |
January 5, 2020, 11:57 |
Monitor digits = 16
|
#1 |
Senior Member
Gert-Jan
Join Date: Oct 2012
Location: Europe
Posts: 1,835
Rep Power: 27 |
Hi All,
I performed a run in double precision with the expert parameter "monitor digits" set to 16. This should give more numbers on axes in the solver manager. But I don't see any effect. Any idea? Anyone over used this option? Regards, Gert-Jan |
|
January 5, 2020, 16:23 |
|
#2 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,723
Rep Power: 143 |
I have never used that option but if you view it through solver manager it might be solver manager truncating it. I would use the command line option to extract the data directly (the command is cfx5mondata I think) or look at the file directly (it is a text file in the solver directory when the run is progressing).
__________________
Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum. |
|
January 6, 2020, 08:20 |
|
#3 |
Senior Member
Gert-Jan
Join Date: Oct 2012
Location: Europe
Posts: 1,835
Rep Power: 27 |
Following your suggestion, I extracted the data from the res file, but it did not make any difference. I asked ANSYS and will update here when possible.
|
|
January 6, 2020, 11:08 |
|
#4 |
Senior Member
Join Date: Jun 2009
Posts: 1,815
Rep Power: 32 |
Did you compare the monitor files (named mon in the running directory) with the default setting, and your setting (=16)?
Are they any different? |
|
January 6, 2020, 14:09 |
|
#5 |
Senior Member
Gert-Jan
Join Date: Oct 2012
Location: Europe
Posts: 1,835
Rep Power: 27 |
If I am informed correctly, it has to do with the Enthalpy being a large number.
In my case I am studying very small temperature differences, and consequently even smaller differences in Enthalpy. When subtracting these large enthalpies, CFX looses relevant digits which is reflected in the temperature that is derived from the enthalpy. |
|
January 6, 2020, 15:22 |
|
#6 |
Senior Member
Join Date: Jun 2009
Posts: 1,815
Rep Power: 32 |
as far as I know, the monitor digits is just a formatting parameter. That is, how many digits are printed out to the monitor file (mon) .
It has nothing to do with precision of the calculations. |
|
January 6, 2020, 15:32 |
|
#7 |
Senior Member
Gert-Jan
Join Date: Oct 2012
Location: Europe
Posts: 1,835
Rep Power: 27 |
This is what I heard through the grapevine. I'm investigating this as we speak.
|
|
|
|