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Field behind metal shield

Martin Hediger
Dear Users
I want to model the following simple case.
Within vacuum, a 2D body carries a surface charge. Next to it is a metal body. I want to obtain the quality of the field direction behind the metal. From theory we know that the metal is not polarizable, i.e. when subject to a field, the charge within separates in order to build up an opposing field within the metal that completely cancels the net field within the metal. The separated charge then produces a field of its own on the opposite side and so the field exits on the opposite side. I tried to model this and show it in this figure:
picturepush.com/public/11036949

My question is:
How do I define the right square to be a metal, i.e. such that the field lines terminate ON the metal on the close side and not "go around it" and then exit on the far side again?

Currently, due to a lack of knowing how to define the metal, I subtract the right rectangle from the vacuum box, but that's not giving the right solution.


Thanks for help.

1 Reply Last Post Oct 12, 2012, 7:53 AM EDT
Posted: 5 years ago Oct 12, 2012, 7:53 AM EDT

You can either assign a PEC (perfect electrical conductor) or impedance boundary condition or add your metal of choice to the materials node and assign the respective domain (the rectangle) to this material. This is all explained in the documentation and in many example model and tutorials.

Cheers
Edgar
You can either assign a PEC (perfect electrical conductor) or impedance boundary condition or add your metal of choice to the materials node and assign the respective domain (the rectangle) to this material. This is all explained in the documentation and in many example model and tutorials. Cheers Edgar

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