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PEC/PMC on the boundaries of the cubic unit cell

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How one can apply the boundary conditions or PEC/PMC on the boundaries of the cubic unit cell if the angle of polarization of the incident electromagnetic wave is rotating? For example, the angle changes from 0 to 90 degrees with an interval of 10 degrees.


3 Replies Last Post Sep 20, 2018, 2:40 p.m. EDT
Robert Koslover Certified Consultant

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Posted: 6 years ago Sep 16, 2018, 6:08 p.m. EDT
Updated: 6 years ago Sep 16, 2018, 6:15 p.m. EDT

In most geometries, such as in a cube, those boundaries would be inconsistent with a rotating field. The PEC boundary will not support a tangential component of E. The PMC boundary will not support a tangential component of H. You need to decide what you are actually trying to model. Is it the rotating field? If so, then you need to choose boundaries that correspond to that. Or is it the certain PEC and PMC boundaries that you want to preserve? Then you need to expect, input, and/or solve for fields that will be consistent with those boundaries.

Note: If your goal is to impose a plane wave at an arbitrary angle inside the cube, consider using the "scattered field formulation." (Look in Settings, under EM Waves, Frequency Domain.) In that approach, you specify a volumetric background field instead, and this simplifies the work you need to do in regard to setting up the boundary conditions.

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Scientific Applications & Research Associates (SARA) Inc.
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In most geometries, such as in a cube, those boundaries would be inconsistent with a rotating field. The PEC boundary will not support a tangential component of E. The PMC boundary will not support a tangential component of H. You need to decide what you are actually trying to model. Is it the rotating field? If so, then you need to choose boundaries that correspond to that. Or is it the certain PEC and PMC boundaries that you want to preserve? Then you need to expect, input, and/or solve for fields that will be consistent with those boundaries. Note: If your goal is to impose a plane wave at an arbitrary angle inside the cube, consider using the "scattered field formulation." (Look in Settings, under EM Waves, Frequency Domain.) In that approach, you specify a volumetric background field instead, and this simplifies the work you need to do in regard to setting up the boundary conditions.

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Posted: 6 years ago Sep 18, 2018, 2:54 a.m. EDT

Thank you Sir. It will be really useful info.

Thank you Sir. It will be really useful info.

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Posted: 6 years ago Sep 20, 2018, 2:40 p.m. EDT

Sir, Could you please guide me in such a case which boundary conditions are suitable? I want to calculate reflection or S11 parameter by applying port 1 for excitation of the plane wave, but bit confuse about choosing the right BCs since the field is rotating.

Sir, Could you please guide me in such a case which boundary conditions are suitable? I want to calculate reflection or S11 parameter by applying port 1 for excitation of the plane wave, but bit confuse about choosing the right BCs since the field is rotating.

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