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Conductive Media DC(shell) + Electrostatics

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hello

I have been trying to couple the two application modes to find the electrostatic force on one boundary at a fixed voltage due to the voltage on a parallel boundary which has a variable voltage along it due to current flowing in it.I am using comsol 4.1.I keep getting the error
"Constraint found for variables in different Segregated groups. Try to merge these groups."

I thing this basically means both the applications are trying to set the voltage along the current flowing boundary.I think so because when I dont link the DC Shell output voltage to Electrostatics I do not get this error.Does anyone know how to get around this or know any other way to calculate this force.I am using Structural Mechanics module,MEMS module, and AC/DC module.

Any comments are appreciated.

thank you


2 Replies Last Post 18 oct. 2012, 07:41 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 janv. 2011, 04:09 UTC−5
Hi

I beleive it's related to the way these physics (which ones in particular: "solid", and ? and "mef" ?) couple and the segregation seqquence proposed.
Try to understand the segregation logic and its implication, often its enough to merge two ne step (if more than 2)

--
Good luck
Ivar
Hi I beleive it's related to the way these physics (which ones in particular: "solid", and ? and "mef" ?) couple and the segregation seqquence proposed. Try to understand the segregation logic and its implication, often its enough to merge two ne step (if more than 2) -- Good luck Ivar

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Posted: 1 decade ago 18 oct. 2012, 07:41 UTC−4
I had the same problem. It was due to an inverted mesh element in my geometry. Creating a finer mesh solved the issue.
I had the same problem. It was due to an inverted mesh element in my geometry. Creating a finer mesh solved the issue.

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