Menu

Discussion Forum

New Discussion
Filter

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

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.

Joule Heating- 3D Rectangular Bar

Posted Dec 19, 2012, 4:28 p.m. EST Electromagnetic Heating, Heat Transfer & Phase Change, Studies & Solvers Version 4.3a 3 Replies

Sowmya Kris
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

I have 3D model of a rectangular Copper bar with 3 rods attached to it. These 3 rods provide electric energy to heat the rod. I am not sure what is incorrect with the case set-up, asI have run a very similar case set-up in a different modeling code, and I get the error 'Unable to solve for T'. Ideally I would like to include Real and Imaginary components of Amps (as a current density input).
Any suggestions will be appreciated. Thanks!
3 Replies Last Post Dec 20, 2012, 1:46 p.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Dec 20, 2012, 2:21 a.m. EST
Hi

this is because you have certainly played with your model and added and deleted a few times some physics, therefore your current physics is solving for "T2" and not "T". When you select several physics with the same dependent variable COMSOL renames then T2, T3 ...

Then for some reason the Results node were kept, so you have two referring to T and not T2. The error message comes from the Results, you case solves OK, see the last Temperature (JH) node

--
Good luck
Ivar
Hi this is because you have certainly played with your model and added and deleted a few times some physics, therefore your current physics is solving for "T2" and not "T". When you select several physics with the same dependent variable COMSOL renames then T2, T3 ... Then for some reason the Results node were kept, so you have two referring to T and not T2. The error message comes from the Results, you case solves OK, see the last Temperature (JH) node -- Good luck Ivar
Sowmya Kris
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Dec 20, 2012, 7:55 a.m. EST
You are right. I did play around with the case a few times- I initially had fluid flow and HT case, to which I removed the fluid flow and did a pure Joule heating case (now I intend to add the flow inside the larger rectangular bar.)

I did not know that Comsol renames the temperatures in this manner- I will watch out for it in the future. Thanks for your help!
You are right. I did play around with the case a few times- I initially had fluid flow and HT case, to which I removed the fluid flow and did a pure Joule heating case (now I intend to add the flow inside the larger rectangular bar.) I did not know that Comsol renames the temperatures in this manner- I will watch out for it in the future. Thanks for your help!
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Dec 20, 2012, 1:46 p.m. EST
Hi

Its worth to check regularly the dependent varaibles and the equations for all physics, open the tabs (see preferences)

--
Good luck
Ivar
Hi Its worth to check regularly the dependent varaibles and the equations for all physics, open the tabs (see preferences) -- Good luck Ivar

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