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Undefined value found

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I had great trouble meshing a geometry. After I refined the mesh and was finally able to mesh it, I clicked the compute button. 78 seconds later, I got this message:

Undefined value found.
- Detail: Undefined value found in the equation residual vector.
.There are 1 degrees of freedom giving NaN/Inf in the vector for the variable mod1.emw.S1x
. at coordinates: (0,0,0), ...
There are 1 degrees of freedom giving NaN/Inf in the vector for the variable mod1.emw.S2x
. at coordinates: (0,0,0), ...

There is also a warning:

Inverted mesh element near coordinates (1.08012e-007, 3.25e-008, 6.4316e-007).

Can anyone help me with this? What's the problem? What should I do?

4 Replies Last Post 2017年6月22日 GMT-4 16:16
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2013年3月1日 GMT-5 03:39
Hi

from the error message it's as if some material data is missing, and or perhaps some domain not meshed (only their boundaries ?)

The inverted mesh warning, is not too tough, as if the model is detailed, the mesh becomes easily poor in some regions (check the statistics of the mesh) and then COMSOL reduces the discretization locally, which means that the results locally might be not very good. But a too poor mesh can also fully invert the "linear" case then it's really becoming locally wrong ;)

Sometimes you can improve the mesh by cutting up your parts into smaller items, isolating small features, by layers, and if possible, start to de-feature (remove all chamfers, holes etc that have no true effect on your model)


--
Good luck
Ivar
Hi from the error message it's as if some material data is missing, and or perhaps some domain not meshed (only their boundaries ?) The inverted mesh warning, is not too tough, as if the model is detailed, the mesh becomes easily poor in some regions (check the statistics of the mesh) and then COMSOL reduces the discretization locally, which means that the results locally might be not very good. But a too poor mesh can also fully invert the "linear" case then it's really becoming locally wrong ;) Sometimes you can improve the mesh by cutting up your parts into smaller items, isolating small features, by layers, and if possible, start to de-feature (remove all chamfers, holes etc that have no true effect on your model) -- Good luck Ivar

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Posted: 10 years ago 2014年11月3日 GMT-5 02:24
Hi,I encountered a problem with emw.s1x.
I defined the PI's two port, & comsol told me the same message as you. Could you share the solution with me?Thank U!
Hi,I encountered a problem with emw.s1x. I defined the PI's two port, & comsol told me the same message as you. Could you share the solution with me?Thank U!

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Posted: 7 years ago 2017年1月26日 GMT-5 05:50
Hi Ray
please how did you resolve this problem!!
can you help me because it look like the same problem
Hi Ray please how did you resolve this problem!! can you help me because it look like the same problem

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Posted: 7 years ago 2017年6月22日 GMT-4 16:16
I had this problem and was able to solve it by assigning a material to the interior boundaries. This wasn't necessary in 5.0.

Sami
I had this problem and was able to solve it by assigning a material to the interior boundaries. This wasn't necessary in 5.0. Sami

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