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Is an insulator boundary same as a floating potential boundary?

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Hi,
I'm a beginner. And i want to create a simulation of electric field distribution. I am using a method of parallel plates. One of plates is an insulator boundary. But in the boundary menu, there is no an insulator boundary. I am trying to use a floating potential boundary because i think it same as an insulator boundary. Is my opinion true or false?

Thank you

2 Replies Last Post 5 sept. 2016, 21:26 UTC−4
Robert Koslover Certified Consultant

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Posted: 8 years ago 3 sept. 2016, 10:53 UTC−4
A floating potential boundary is also an equipotential. This means that the electric field must have no tangential component on that boundary. Electrical insulation does not impose that constraint, per se. However, if it is your intention to prepare an electrostatic model an electric conductor that is immersed in an insulating medium (such as might be the case in some capacitor problems), then it may be appropriate to assign that conductor a floating potential.

Another note: Sometimes, the best way to compare/choose from among the different boundary conditions is to look at the actual equations used by Comsol for the boundary conditions offered. These equations are not always obvious based on the names alone.
A floating potential boundary is also an equipotential. This means that the electric field must have no tangential component on that boundary. Electrical insulation does not impose that constraint, per se. However, if it is your intention to prepare an electrostatic model an electric conductor that is immersed in an insulating medium (such as might be the case in some capacitor problems), then it may be appropriate to assign that conductor a floating potential. Another note: Sometimes, the best way to compare/choose from among the different boundary conditions is to look at the actual equations used by Comsol for the boundary conditions offered. These equations are not always obvious based on the names alone.

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Posted: 8 years ago 5 sept. 2016, 21:26 UTC−4
Thank you, Mr. Robert Koslover

Your reply had solved my problem. Now, I know the meaning of a floating potential.
Thank you, Mr. Robert Koslover Your reply had solved my problem. Now, I know the meaning of a floating potential.

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