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Current in Electrostatics physics

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Hi

I need to work in electrostatic physics because I should define some charges and I need to have surface charge density option (Which is available in this physics)

However, When i define a simple system (2 electrodes+ a conductive medium on top and between electrodes) I will not have any current density result (it is zero) I can't understand this because since the medium is conductive I should have a current)!!

anybody has any idea?

Best
Bahar


2 Replies Last Post Jan 6, 2012, 5:38 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jan 5, 2012, 3:14 a.m. EST
Hi

if you read carefully the first lines in the help files for ES and for EC physics, you will see that the first solves for charge conservation, the second for current conservation. You see also the difference if you open the main physics node "equation"

So you get no currents in ES (anyhow the material DB does not use the resistivity only the permittivity).

So for your case I suppose you need to integrate or define differently/indirectly you change densities in EC to get the full image (now I'm not sure I understand fully what you want to do anyhow ;)

--
Good luck
Ivar
Hi if you read carefully the first lines in the help files for ES and for EC physics, you will see that the first solves for charge conservation, the second for current conservation. You see also the difference if you open the main physics node "equation" So you get no currents in ES (anyhow the material DB does not use the resistivity only the permittivity). So for your case I suppose you need to integrate or define differently/indirectly you change densities in EC to get the full image (now I'm not sure I understand fully what you want to do anyhow ;) -- Good luck Ivar

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Posted: 1 decade ago Jan 6, 2012, 5:38 a.m. EST
Hi Sir ,
i was also hear to clear my doubt but you helped me lot and i am trying it to find and will ask if there will be problem. Thanks for this solution .
Hi Sir , i was also hear to clear my doubt but you helped me lot and i am trying it to find and will ask if there will be problem. Thanks for this solution .

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