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Non-zero divergence of D and B fields in ewfd Mode Analysis
Posted 29 set 2017, 14:29 GMT-4 Wave Optics Version 5.3 1 Reply
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I am solving for the mode of a silicon nanowire. I am interested in the bound current and bound charge distributions within the waveguide, as I would like to evaluate the electromagnetically induced mechanical forces within the structure.
I have investigated the charge and current densities, and was not satisfied with the results. The divergence of the D and B fields is non-zero (attached) -- which is a non-physical result. Refinements to the mesh do not cause these quantities to converge to zero.
The reason the divergences is non-zero is due to the master equation for the Wave Equation physics interface does not require them to be. Is there a way to transform these solutions to satisfy these constraints? Is it possible to constrain the solver to set these quantities to zero?
Hello Warren Jin
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I was calculating the divergence incorrectly. The Bz field has no spatial variation in 2D symmetry, the correct expression is:
d(ewfd.Bx,x)+d(ewfd.By,y)+lambda*ewfd.Bz