Menu

Discussion Forum

New Discussion
Filtrer

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Determine time at which a certain temperature is reached

Posted 10 juin 2022, 04:41 UTC−4 Results & Visualization, Studies & Solvers Version 5.6 2 Replies

Nils Ellendt
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Dear all,

it appears I have a fairly simple question.

I am doing a paramteric study with around 200 variations of geoemtric parameters for a solid cooling problem. I am focussing on a specific point (identified in the geometry as a point for easy selection) for which I obtain the thermal history as T(t).

Now I would like to determine that time at which a certain temperature was reached. I am struggeling a bit, since I was not able to obtain an automated data export for the T(t) of that point since the meshes are different. If this was possible, I would let Matlab or Python do the rest of the job.

On the other hand, I was not able to get the result with "derived values" as a table for each parameter variation (which would be really cool).

Did I miss a feature?

Nils

2 Replies Last Post 13 juin 2022, 01:45 UTC−4
David Ashirov
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 3 years ago 12 juin 2022, 15:04 UTC−4

Hello Nils You plot your temperature curves T(t) using 1D plot group, adding Point plot and specifying your expression there. Then you can open Results tab, click Data drop down list and select Plot. This action will create a plot export feature. You should specify your 1D plot group there and export the data to a file.

Another option would be to create a global evaluation and enter the following expression: attimemin(0, t, abs(T(s) - T_desired), t) where T_desired is the certain temperature you mentioned. This expression works by finding the time when the absolute value of T(s) - T_desired is at the minimum and returning the time. However if T(s) crosses T_desired several times or doesn't cross it, it will return a single time value. It is the drawback.

Hello Nils You plot your temperature curves T(t) using 1D plot group, adding Point plot and specifying your expression there. Then you can open Results tab, click Data drop down list and select Plot. This action will create a plot export feature. You should specify your 1D plot group there and export the data to a file. Another option would be to create a global evaluation and enter the following expression: attimemin(0, t, abs(T(s) - T_desired), t) where T_desired is the certain temperature you mentioned. This expression works by finding the time when the absolute value of T(s) - T_desired is at the minimum and returning the time. However if T(s) crosses T_desired several times or doesn't cross it, it will return a single time value. It is the drawback.
Nils Ellendt
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 3 years ago 13 juin 2022, 01:45 UTC−4

Thank you David!

The export from the plot did not work due to "different meshes" which was really confusing to me.

The second approach worked well and is actuall what I wanted to do :-)

Thank you David! The export from the plot did not work due to "different meshes" which was really confusing to me. The second approach worked well and is actuall what I wanted to do :-)

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content