Support Floquet periodic boundary conditions #314
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Looking pretty good, I think there are a few larger changes to take care of first
- FP should be part of K, given it has no omega dependence in its construction unlike A2. This will simplify loads of things
- The muinv kx should be in the MaterialOperator, (doing this neatly will mean adding the ability to use transpose coefficients in the ceed context)
- The geodata.cpp can be shortened and simplified some, I have some initial work on doing this in
hughcars/periodic-bc, but I'm sure once you get started you'll probably see even more things to do. The basic thing is a mixing assumptions on sdim and no assumptions on sdim.
| distance between them is given by the `"Translation"` vector in mesh units. In `floquet.json`, | ||
| an additional `"FloquetWaveVector"` specifies the phase delay between the donor and receiver | ||
| boundaries in the X/Y/Z directions. |
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Given the relative simplicity of this example, it would be great if we can derive the expected modes analytically. I suspect it'll be possible to map them to an equivalent set of modes on a full length cylinder without phase shift, at which point analytic results can be compared against like for the waveguide case.
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I compared the cylindrical waveguide modes (as well as a rectangular waveguide and a nail/pillar) against Comsol and they all matched so I feel confident about it, but I'll see if I can derive analytical modes for the Floquet case.
| @@ -74,7 +74,7 @@ Periodic boundary conditions on an existing mesh can be specified using the | |||
| ["Periodic"](../config/boundaries.md#boundaries%5B%22Periodic%22%5D) boundary keyword. This | |||
| boundary condition enforces that the solution on the specified boundaries be exactly equal, | |||
| and requires that the surface meshes on the donor and receiver boundaries be identical up to | |||
| translation. Periodicity in *Palace* is also supported through meshes generated | |||
| translation or rotation. Periodicity in *Palace* is also supported through meshes generated | |||
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How have you tested the rotational case? Might make for a cool example, thinking plausibly the waveguide cylinder could be split into wedges maybe and analyzed.
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I tested the pure rotation with an annulus wedge and the rotation + translation case with a helical case.
Add support for Floquet periodic boundary conditions and improve flexibility of periodic boundary conditions specifications.