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Electrostatics: relative permittivity

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Hi,

I am solving an electrostatics model which includes conducting and insulating material. What is the relative permittivity value of conducting material used? All the in built materials use the value as '1' for epsilon; where it should be infinity in theory. Also, I am getting the correct answer using it as '1', but that would be incorrect as I am ignoring the shielding in conductors in this case.

Do the relative permittivity have its usual meaning in COMSOL?

Thanks,
K

2 Replies Last Post 18 févr. 2016, 12:26 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 6 mai 2013, 01:32 UTC−4
Hi

normally you would not consider "conducting" materials in EC (just its boundaries), as the current flow is not resolved in ES (for that you need EC), but you can set a large epsilon_r value to your metals to mimic the "static conduction"

If you use epsilon_r=1 then you get a voltage drop across your conductor that is not really physical

--
Good luck
Ivar
Hi normally you would not consider "conducting" materials in EC (just its boundaries), as the current flow is not resolved in ES (for that you need EC), but you can set a large epsilon_r value to your metals to mimic the "static conduction" If you use epsilon_r=1 then you get a voltage drop across your conductor that is not really physical -- Good luck Ivar

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Posted: 9 years ago 18 févr. 2016, 12:26 UTC−5
Hi,

I have a similar problem, I`m studying the crosstalk (variation of voltage) between two electrical gold traces. The voltage on the victim trace vary in function of the relative permittivity.
How can I be precise in the choice of his value?
Unfortunately it is not enough to be precise just choose a random big number.

Thanks,

Rafael
Hi, I have a similar problem, I`m studying the crosstalk (variation of voltage) between two electrical gold traces. The voltage on the victim trace vary in function of the relative permittivity. How can I be precise in the choice of his value? Unfortunately it is not enough to be precise just choose a random big number. Thanks, Rafael

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