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Convergence Problems with Two-Phase Mixture Model in porous media

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Dear colleagues,

I am an amateur in working with COMSOL. I try to simulate a two-phase flow with phase change for a simple 1D case. The problem description is the same as in [1], but for 1D. The PDE's are implemented with the PDE-mode.

The model works fine if the temperature doesn't rise above the boiling point, but then the computation fails. I think the problem is the discontinuity in the derivation of the temperature.

So far I tried:

- to smooth this function, which works in some cases, but the results are nocht realistic
- to use a segregated solver
- to use direct or/and iterative solver (where do I find a nice overview, which solver serves me best?)
- different mesh sizes
- changing BC for the energy equation (Dirichlet or Neuman)

The model in comsol is attached.


Thanks in advance
David

Version: COMSOL 4.1



[1] C.Y. Wang - A Fixed-Grid numerical algorithm for two-phase flow and heat transfer in porous media





0 Replies Last Post 26 avr. 2012, 07:03 UTC−4
COMSOL Moderator

Hello David Droste

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