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 The information provided may be out of date.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.

Electric Currents simulation => Singular Matrix

Please login with a confirmed email address before reporting spam

Hello !

I'm facing a problem of 'Singular Matrix', I've tried to modified the mesh, all the materials are well defined... so I don't understand. It is the first time I met this kind of error.

I thank you in advance for helping me :)


4 Replies Last Post Jul 5, 2012, 4:55 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Jul 4, 2012, 5:55 p.m. EDT
Hi

I do not believe it's a mesh issue, rather some missing BCs not making your model unique. Check that all dependent variables have enough BC defining it unambiguisly

--
Good luck
Ivar
Hi I do not believe it's a mesh issue, rather some missing BCs not making your model unique. Check that all dependent variables have enough BC defining it unambiguisly -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Jul 5, 2012, 2:58 a.m. EDT
Hi!

Set the conductivity of air to 1 S/m, then it will run.
COMSOL default for air conductivity is zero...why?

Ralf
Hi! Set the conductivity of air to 1 S/m, then it will run. COMSOL default for air conductivity is zero...why? Ralf

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Jul 5, 2012, 3:09 a.m. EDT
Hi

good point, never forget to REcheck your materials, when you have finished setting up your model, often new demands appear when you tweak your physics settings, andone forget to update the materials. And if you have current flowing, you need to have some conductivity eveerywhere in the conduxtion domain

--
Good luck
Ivar
Hi good point, never forget to REcheck your materials, when you have finished setting up your model, often new demands appear when you tweak your physics settings, andone forget to update the materials. And if you have current flowing, you need to have some conductivity eveerywhere in the conduxtion domain -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Jul 5, 2012, 4:55 a.m. EDT
Hi,

I trust too much default settings :)

Thank you very much !
Hi, I trust too much default settings :) Thank you very much !

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.