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Undefined value found for Joule Heating and Thermal Expansion

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I'm trying to study how a material expands when applying a short Voltage pulse.

So I'm using Joule Heating and Thermal expansion and trying to solve it time dependent. I made a cylinder and specified ground on one side (which is also fixed) and a rectangle voltage pulse on the other side, however i get some errors that I don't really understand:


Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
There are 5745 equations giving NaN/Inf in the matrix rows for the variable mod1.u
at coordinates: (-0.000108515,-6.20447e-005,0.002), (-8.83875e-005,-8.83892e-005,0.002), (-6.20426e-005,-0.000108516,0.002), (-8.18416e-005,-6.0695e-005,0.002), (-5.51684e-005,-5.93454e-005,0.002), ...
There are 5745 equations giving NaN/Inf in the matrix rows for the variable mod1.v
at coordinates: (-0.000108515,-6.20447e-005,0.002), (-8.83875e-005,-8.83892e-005,0.002), (-6.20426e-005,-0.000108516,0.002), (-8.18416e-005,-6.0695e-005,0.002), (-5.51684e-005,-5.93454e-005,0.002), ...
There are 5745 equations giving NaN/Inf in the matrix rows for the variable mod1.w
at coordinates: (-0.000108515,-6.20447e-005,0.002), (-8.83875e-005,-8.83892e-005,0.002), (-6.20426e-005,-0.000108516,0.002), (-8.18416e-005,-6.0695e-005,0.002), (-5.51684e-005,-5.93454e-005,0.002), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns


Any suggestions on how to proceed?

0 Replies Last Post 2010年11月19日 GMT-5 07:37
COMSOL Moderator

Hello Micke Malmström

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