awslabs / palace

3D finite element solver for computational electromagnetics
https://awslabs.github.io/palace/dev
Apache License 2.0
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Transient waveport boundary condition #243

Open Wayne901 opened 2 months ago

Wayne901 commented 2 months ago

Hi there. I was learning MFEM to implement some transient EM projects. Palace is really experienced with EM problems, so I try to ask for some help here.

It confuses me, to set the waveport boundary condition in transient problem for a rectangular waveguide. TEM mode is easy to apply as an impedance BC, but TE mode and TM modes are frequency dependent. The method proposed in The Finite Element Method in Electromagnetics by Jianming Jin requires convolution, seems a bit complex. How does palace, or commercial softwares such as COMSOL address it?

sebastiangrimberg commented 1 month ago

Hi @Wayne901, thanks for opening this issue. In Palace, the wave port boundary condition is actually only implemented for frequency domain problems and not in the time domain. I believe you are correct that in general, the wave port boundary for transient simulations would require a convolution as described in the Jin textbook. There may be better ways to do it, however.

We would definitely welcome contributions to add this type of functionality to Palace and could provide help where needed for the implementation.

Wayne901 commented 1 month ago

I just moved from frequency domain problems to time domain ones. The waveport boundary is tricky in time domain... Thank you for your reply.