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.

Using form assembly and gravity

Please login with a confirmed email address before reporting spam

I’m using form assembly in a model because I want one domain to slide across another. On the bottom of the upper domain, I have prescribed displacement in the y direction but not in the x or z direction. However I also have gravity acting on both domains. This causes the upper domain to fall all the way through the bottom one. How can I prevent this from happening?

Prescribing a z displacement of 0 on the boundary keeps this from happening, but then the boundary of the upper domain isn't free to deform around bumps in the lower one as it slides in the y direction. I’ve tried setting up an identity boundary pair between them, which prevents this problem, but I don’t want to use a pair boundary condition because I don’t want to have a prescribed velocity on the boundary of both domains, just the upper one. I’ve also tried having one side boundary of the upper domain be fixed, which seems to prevent this problem, but that’s not actually the boundary condition I want to have there.



0 Replies Last Post 19.06.2020, 13:49 GMT-4
COMSOL Moderator

Hello Claire Cook

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.