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What does the error ''Undefined value found in the stiffness matrix''?

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Hi:

Sorry for bothering.

I have built up a ComSol model for calculating eigenfrequency of a ring resonator. However, it gives me the following error when I compute:

Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
There are 1640 equations giving NaN/Inf in the matrix rows for the variable mod1.Ez
at coordinates: (-3e-006,-3e-006), (-2.94713e-006,-2.94389e-006), (-2.89427e-006,-2.88778e-006), (-2.91667e-006,-3e-006), (-2.8638e-006,-2.94389e-006), ...
There are 2352 equations giving NaN/Inf in the matrix rows for the variable mod1.tExEy10
at coordinates: (-2.96476e-006,-2.96259e-006), (-2.92951e-006,-2.92519e-006), (-2.94444e-006,-3e-006), (-2.87395e-006,-2.92519e-006), (-2.88889e-006,-3e-006), ...
There are 712 equations giving NaN/Inf in the matrix rows for the variable mod1.tExEy20
at coordinates: (-2.9092e-006,-2.96259e-006), (-2.96476e-006,-2.90704e-006), (-2.92739e-006,-2.82377e-006), (-2.82683e-006,-2.91375e-006), (-2.84502e-006,-2.83048e-006), ...
There are 712 equations giving NaN/Inf in the matrix rows for the variable mod1.tExEy21
at coordinates: (-2.9092e-006,-2.96259e-006), (-2.96476e-006,-2.90704e-006), (-2.92739e-006,-2.82377e-006), (-2.82683e-006,-2.91375e-006), (-2.84502e-006,-2.83048e-006), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns

So does this means that the ComSol model is correct, but the simulation result found some singular point or what?

I have attached the ComSol model file in the attachment.

Thanks so much for your time.


1 Reply Last Post 8 giu 2011, 11:27 GMT-4
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Hello jie zheng

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Posted: 1 decade ago 8 giu 2011, 11:27 GMT-4
I encountered the same error, but still cannot fix it. Have you work it out?
I encountered the same error, but still cannot fix it. Have you work it out?

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