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Boundary condition for finding the Eigenfrequencies of a simple cavity in RF
Posted Feb 6, 2013, 11:34 a.m. EST RF & Microwave Engineering, Studies & Solvers Version 4.2a 0 Replies
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Hi,
I'm trying to find the eigenfrequencies of a simple cavity in 2D/3D. I put my cavity in a large circle/sphere. now to find the eigenfrequencies, i put the scattering boundary condition for the outer most layer, and add PML. The program stop running cause it founds some NAN/Inf values on the boundary of the outermost layer. the problem would solve if i remove the scattering boundary condition and just use PML, but in this case it would give me some modes outside the cavity in free space! I'm new in COMSOL, I tried to checked the examples in RF session but couldn't find "Eigenfrequency" regimes. they all use frequency domains and has initial values for the field at the boundaries. So my question is can i even use the scattering boundary condition in resonance frequency finding where there is no source or initial value anywhere in the system?
Thanks
Hello Parinaz Aleahmad
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