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 The information provided may be out of date.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.

singularity error from plasma simulation

Please login with a confirmed email address before reporting spam

Hi there,

I'm doing a plasma-polymer surface simulation. I used a fluid dynamic model, with mass transportation model to analyse the concentration of Atomic oxygen in the environment. However, during the simulation, I always encounter singularity error(I used time dependent direct solver). Although this problem can be avoided by using extra coarse mesh, the result doesn't provide enough resolution of atomic oxygen near the bottom wall (if anyone look at the result in the file, he will find a concentration gap near the bottom wall, which is the polymer sample. This is not very physical, and I think this is caused by large mesh size). But if I refine the mesh, singularity errors will pop out. Can anyone help me solve this problem? Thanks in advance.

Attachment is my geometry: upper geometry is plasma source, no kinetics has been build in there. Lower geometry is effluent or the chamber, with bottom wall be my sample surface. (certain loss rate has been set near the bottom wall)

Sincerely,
Haotian


0 Replies Last Post Sep 16, 2016, 3:11 p.m. EDT
COMSOL Moderator

Hello Haotian Wang

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.

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.