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Electric Currents simulation => Singular Matrix

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Hello !

I'm facing a problem of 'Singular Matrix', I've tried to modified the mesh, all the materials are well defined... so I don't understand. It is the first time I met this kind of error.

I thank you in advance for helping me :)


4 Replies Last Post 5 juil. 2012, 04:55 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 4 juil. 2012, 17:55 UTC−4
Hi

I do not believe it's a mesh issue, rather some missing BCs not making your model unique. Check that all dependent variables have enough BC defining it unambiguisly

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Good luck
Ivar
Hi I do not believe it's a mesh issue, rather some missing BCs not making your model unique. Check that all dependent variables have enough BC defining it unambiguisly -- Good luck Ivar

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Posted: 1 decade ago 5 juil. 2012, 02:58 UTC−4
Hi!

Set the conductivity of air to 1 S/m, then it will run.
COMSOL default for air conductivity is zero...why?

Ralf
Hi! Set the conductivity of air to 1 S/m, then it will run. COMSOL default for air conductivity is zero...why? Ralf

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 5 juil. 2012, 03:09 UTC−4
Hi

good point, never forget to REcheck your materials, when you have finished setting up your model, often new demands appear when you tweak your physics settings, andone forget to update the materials. And if you have current flowing, you need to have some conductivity eveerywhere in the conduxtion domain

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Good luck
Ivar
Hi good point, never forget to REcheck your materials, when you have finished setting up your model, often new demands appear when you tweak your physics settings, andone forget to update the materials. And if you have current flowing, you need to have some conductivity eveerywhere in the conduxtion domain -- Good luck Ivar

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Posted: 1 decade ago 5 juil. 2012, 04:55 UTC−4
Hi,

I trust too much default settings :)

Thank you very much !
Hi, I trust too much default settings :) Thank you very much !

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