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Band diagram of 3D periodic photonic crystals

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Hi,

I try to calculate band diagram for 3D photonic crystal using RF module (version 4.4). At first, for the sake of simplicity, I plot a cubic unit cell and set Floquet boundary conditions (3 pairs). Then I solve eigenvalue problem using Bloch vector components as parameters.

When I start the calculation Comsol gives me an ERORR "Inconsistent uni-directional constraint".

In 2D case (square unit cell) all works. What am I doing wrong?

Many thanks in advance!

Andrey


5 Replies Last Post Dec 6, 2016, 2:27 p.m. EST
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Posted: 1 decade ago Jul 18, 2014, 4:13 p.m. EDT
Hi,

I have attempted simulating a 2d phononic band gap structures using the structural mechanics module and floquet periodic boundary conditions on 2 pairs of surfaces, and I am also seeing the error "Inconsistent uni-directional constraint". I noticed that making the mesh finer solves the issue, but I still get occasional errors which hinders me from doing batch simulations

Has anyone else had a similar experience and devised ways to overcome this?
Hi, I have attempted simulating a 2d phononic band gap structures using the structural mechanics module and floquet periodic boundary conditions on 2 pairs of surfaces, and I am also seeing the error "Inconsistent uni-directional constraint". I noticed that making the mesh finer solves the issue, but I still get occasional errors which hinders me from doing batch simulations Has anyone else had a similar experience and devised ways to overcome this?

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Posted: 10 years ago Apr 13, 2015, 12:27 p.m. EDT
Hi, Andrey,
Did you solve that problem? I meet the same problem, could you give me some suggestions? Thank you.

Echo

Hi, Andrey, Did you solve that problem? I meet the same problem, could you give me some suggestions? Thank you. Echo

Radwanul Hasan Siddique

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Posted: 9 years ago Jun 5, 2015, 3:15 p.m. EDT
Hi guys,

I am facing the similar problem. Any solution??

Thanks in advance.

Greetings,
Radwan
Hi guys, I am facing the similar problem. Any solution?? Thanks in advance. Greetings, Radwan

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Posted: 8 years ago Jul 16, 2016, 6:49 p.m. EDT
Hey all,

I found a solution. I have been using this to model 3D photonic crystals with Floquet BCs along one axis, and I kept getting this same error. It went away once I started copying the face from one side of the continuity to the other.

Good luck!
Hey all, I found a solution. I have been using this to model 3D photonic crystals with Floquet BCs along one axis, and I kept getting this same error. It went away once I started copying the face from one side of the continuity to the other. Good luck!

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Posted: 8 years ago Dec 6, 2016, 2:27 p.m. EST
Dear Orad,

I am currently wokrking on the same problem but copying the face from one side of the continuity to the other did not work for me.

Would you be willing to share your model file with me? I would simplify things very much for my.

Kind regards,

Henrik
Dear Orad, I am currently wokrking on the same problem but copying the face from one side of the continuity to the other did not work for me. Would you be willing to share your model file with me? I would simplify things very much for my. Kind regards, Henrik

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