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RF, 3D rib waveguide propagation. The no solution / poor convergence issue.
Posted 14.09.2012, 10:24 GMT-4 RF & Microwave Engineering Version 4.2a 1 Reply
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Hi,
I'm modeling a complex 3D rib waveguide structure. I'm following the examples and solving boundary modes for both ports (1 excited) in study 1, and then choosing the correct mode I want to propagate for a frequency domain analysis in study 2.
Study 2 will not converge. At first it was solving but giving me no solution, and I discovered my mesh size was not fine enough. I think this is a problem a lot seem to be having on these forums, and is why we get 0 field everywhere- The BiCGStab iterative solver just fails at step 0 (doesn't go thru the converging sequence).
So basically I shrunk my propagation distance substancially in order to get a fine enough mesh and reasonable solve time, and now it gets to the BiCGStab iterative sequence, but never converges after 300, 500, 1000 iterations.
It seems something like the waveguide-coupler example, where the structure and input mode are extremely simple, is the only thing that it can propagate?
Any help or discussion would be much appreciated.
-Kevin
I'm modeling a complex 3D rib waveguide structure. I'm following the examples and solving boundary modes for both ports (1 excited) in study 1, and then choosing the correct mode I want to propagate for a frequency domain analysis in study 2.
Study 2 will not converge. At first it was solving but giving me no solution, and I discovered my mesh size was not fine enough. I think this is a problem a lot seem to be having on these forums, and is why we get 0 field everywhere- The BiCGStab iterative solver just fails at step 0 (doesn't go thru the converging sequence).
So basically I shrunk my propagation distance substancially in order to get a fine enough mesh and reasonable solve time, and now it gets to the BiCGStab iterative sequence, but never converges after 300, 500, 1000 iterations.
It seems something like the waveguide-coupler example, where the structure and input mode are extremely simple, is the only thing that it can propagate?
Any help or discussion would be much appreciated.
-Kevin
1 Reply Last Post 17.09.2012, 12:56 GMT-4
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Posted:
1 decade ago
Try direct solver.