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 The information provided may be out of date.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.

weak form PDE modeling of 1D Poisson-Nernst-Planck (PNP) equations

Please login with a confirmed email address before reporting spam

Hello:

I'm learning the Weak Form PDE modeling in Comsol and I want to solve Poisson-Nernst-Planck (PNP) equations by using Weak Form PDE. Although we can solve PNP by using modules of Poisson's equation and Transport of Dilute Species, I still want to solve it by just using PDE module and learn to solve coupled equations in Comsol.

I want to model the time-dependent evolution of an electrolyte under an external electrical field. The equations and boundary conditions are in the attached PDF file and my .MPH file is also attached.

Currently I'm strugling with an error message 'Failed to find consistent initial values.Last time step is not converged'. I don't know where the problem is and I guess there are problems with my weak form implementation. Does anybody know how to resolve this issue? Thanks in advance.


2 Replies Last Post Apr 23, 2014, 10:58 a.m. EDT
COMSOL Moderator

Hello Jamesowl

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.


Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Mar 3, 2014, 9:52 p.m. EST
do you have qq , please join me 695942037 . i meet the problem. can you help me with the PNP model?
do you have qq , please join me 695942037 . i meet the problem. can you help me with the PNP model?

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Apr 23, 2014, 10:58 a.m. EDT
What specific problem you encountered? Could you provide more information?

Thanks.
What specific problem you encountered? Could you provide more information? Thanks.

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.