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solver questions for multiphysics problem with time dependency

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Hi everyone!

I am running the simulations with a fully coupled solver. The physics i use are moving mesh and laminar 2phase flow (phase field). I have a couple of doubts regarding and its listed below:
1- Where can I find out the difference between Direct and Direct1 (linear solver)
2- I read that for time dependent problems, updating the Jacobian ensures stability. So by setting the tolerance factor and relative tolerance to 10^-6, will I make sure that all the dependent variables fall under the given tolerance?
3- For stationary solver, how is the tolerance level set??
4- 'LinErr' 'LinRes' 'Jac' and the other parameters in Log , what are they? or how do i interpret them?

And do you have any tips to check for convergence in this problem?

Thanks a lot for your time!

0 Replies Last Post Feb 10, 2016, 5:08 a.m. EST
COMSOL Moderator

Hello Kurian Vachaparambil

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