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Joule Heating with Thermal Expansion Simple Setup

Brandon Voelker
Good Afternoon Everyone,

I am new to COMSOL but have used other software for simulations (ANSYS), I am currently trying to model an aluminum wire embedded in a polyethylene substrate, just doing a 2D analysis for now. I have created a potential difference for the wire and would like to see the resulting thermal gradient, and the ultimate goal of the stress created between the wire and the substrate.

However when I go to solve I get an error that I have undefined values, I narrowed it down to the polyethylene, but can not find any missing values?

To move past this I temporarily just selected copper as a substrate material, this got past the first error, but a new error appears that there are degrees of freedom (resulting during the mechanical analysis) I have a fixed edge so not sure what else I should have to define.

Attached is the file I have been working with.

Any help would be greatly appreciated.


1 Reply Last Post Jan 18, 2013, 10:02 AM EST
COMSOL Moderator

Hello Brandon Voelker

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Frank van Gool COMSOL Employee
Posted: 5 years ago Jan 18, 2013, 10:02 AM EST
Dear Brandon,

please check forum entry 31019
www.comsol.com/community/forums/general/thread/31019/
where the same error occurs.

You have chosen a poisson's ratio of 0.5 which leads to infinite numbers on the diagonal. Choosing a value of 0.499 will solve your problem.

Best regards,
Frank
Dear Brandon, please check forum entry 31019 http://www.comsol.com/community/forums/general/thread/31019/ where the same error occurs. You have chosen a poisson's ratio of 0.5 which leads to infinite numbers on the diagonal. Choosing a value of 0.499 will solve your problem. Best regards, Frank

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