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Convergence and solving

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If the solution time is long and convergence is goes up and down between certain numbers (E6-E11 in my case), then what does it mean? Will it goes a soln. or not? Can I understand this? I run the problem and it continues about for one hour and convergence changes between the values I mentioned. Now, the run continues. I wonder if the run will finish with an error or not? or this is normal case.

1 Reply Last Post 2011年1月14日 GMT-5 06:49
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2011年1月14日 GMT-5 06:49
Hi

non linear solvers have the tendency to loop around and not converge, when the values are too far from a know good solution. That is why COMSOl has the number of iteration normally set to 25 or a "small" value.

Sometimes it helps to stop it and relaunch it, but mostly it comes from poorly defined (too far from the final solution) BC's, or just a meshing that is too course or ...

It is worth to follow some of the COMSOL courses on solver settings, there are really a lot to learn there too

--
Good luck
Ivar
Hi non linear solvers have the tendency to loop around and not converge, when the values are too far from a know good solution. That is why COMSOl has the number of iteration normally set to 25 or a "small" value. Sometimes it helps to stop it and relaunch it, but mostly it comes from poorly defined (too far from the final solution) BC's, or just a meshing that is too course or ... It is worth to follow some of the COMSOL courses on solver settings, there are really a lot to learn there too -- Good luck Ivar

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