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Assigning electric potential

Michele Adriano Di Monte

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Hi,
we are having trouble in solving this simple problem:

to assign an elettric potential and a ground to the extremity of a coil the is inside an air sphere (see attached model "example1.mph".

This is the error message we got from comsol solver:

Failed to find a solution.
Singular matrix.
For mesh-case 0 there are 29182 void equations (empty rows in matrix) for the variable mod1.V
at coordinates: (0.499384,0.0364705,0.0103258), (0.49923,0.0367934,0.0106871), (0.498941,0.0367463,0.0103436), (0.499489,0.0370084,0.0103114), (0.500466,0.028009,0.0103919), ...
and similarly for the degrees of freedom (empty columns in matrix)
Returned solution has not converged.

Thank you
Adriano


2 Replies Last Post 26.10.2011, 10:41 GMT-4

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Posted: 1 decade ago 26.10.2011, 10:20 GMT-4
Hi,

Why the air does not surround all the coil? So it is not "a coil the is inside an air sphere".
Hi, Why the air does not surround all the coil? So it is not "a coil the is inside an air sphere".

Michele Adriano Di Monte

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Posted: 1 decade ago 26.10.2011, 10:41 GMT-4
I tried to assign the electric potential having the coil completely in air but the electric potential menu shows (NOT APPLICABLE). How can I solve this problem?
I tried to assign the electric potential having the coil completely in air but the electric potential menu shows (NOT APPLICABLE). How can I solve this problem?

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