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Undefined value found in the equation residual vector.

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Undefined value found.

  • Detail: Undefined value found in the equation residual vector.
  • There are 66 degrees of freedom giving NaN/Inf in the vector for the variable comp1.phil. at coordinates: (0.00825542,0.00128606,0.005028), (0.008,0.001,0.005028), (0.008,0.0014,0.005028), (0.00825542,0.00128606,0.00503061), (0.008,0.001,0.00503061), ...

There are 66 degrees of freedom giving NaN/Inf in the vector for the variable comp1.phis. at coordinates: (0.00825542,0.00128606,0.005028), (0.008,0.001,0.005028), (0.008,0.0014,0.005028), (0.00825542,0.00128606,0.00503061), (0.008,0.001,0.00503061), ...

I solve a multiphysics coupled SOFC with mass, heat, momentum transfer, and electrochemical reaction.

It solved smoothly with electrochemical and momentum transport and also solved with anode mass transport.However, when I coupled mass transfer of cathode it reports an error like above.

When I decoupled reaction in cathode mass transport, it solved. When I reduce the reaction multiply by 0.1 it also solved. Increase reaction will cause the same error.

Besides, the coordinates don't in the solution domain. I wonder if anyone could help me to figure out what should I do without compromise in reduced reaction in mass transport?

Also, When I use reduced reaction coupled with heat transfer, the same error appeared.

The cathode anode and electrolyte are just 20, 30, and 8 um thick.

With great appreciation.

Kind regards,

Xiaoqiang


0 Replies Last Post Jun 5, 2020, 5:32 a.m. EDT
COMSOL Moderator

Hello Xiaoqiang zhang

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