HFSS- Boundaries overlapping error... master/slave with perfect E

[violetcrow]

I could not find a solution on here, so I post a new thread.

I have a floquet port design where the object (unit cell with perfect E boundary) overlaps with a master and slave boundary of region. I wanted to remove objects face which overlaps with the master/slave face, but it seems it would violet the object to retain its material (here copper). I have not been able to remove the boundary overlapping error, and any suggestion is extremely appreciated.

 

[simuboss]

the geometry you've made is probably not right. let's take a look at snapshot of your model...

 

[violetcrow]

the geometry you've made is probably not right. let's take a look at snapshot of your model...

I attached snapshots, hope they are clear. I have an extended object which its arms touche the periodic boundaries. The second pic shows the the small face of object at the end of one of its arms which touches the face of region. I am not sure how much this boundaries overlapping can affect the whole simulation results.

 

[simuboss]

are u getting errors or results are weird? if that is copper u will have currents flowing around the boundary...

 

[violetcrow]

are u getting errors or results are weird? if that is copper u will have currents flowing around the boundary...

The error is boundary overlapping error when performing validation check. Results are not weird for this case, as I am looking for S parameters only (reflection and transmission), but still a little different from the one I have from COMSOL. Now the overlap boundaries are pretty small, so perhaps don't affect the results much, but I am more concerned about other configurations which there will be more overlapped boundaries. I have not been able to find any note on this situation in HFSS full book, so I wanted to know how we should approach the error generally, especially in the case of extended objects in periodic boundaries.

Yes, it is copper.

 

[simuboss]

So, maybe the comsol one is different from HFSS! Do you get the same error in comsol?
for these cases, I can think of two solutions. first is to use equivalent fields and currents in your model. So you need to find the response of cross section of copper and the BC, then add an equivalent element to the model to compensate for the overlap. this is much more accurate. try this first...

 

[violetcrow]

o, COMSOL does not give overlapping errors, it is a little difference since I can define faces which I want to be repeated. The overall results are pretty much the same, HFSS and COMSOL. But in more sophisticated configurations, there are some differences. I will try your suggestion, will let you know. Thanks

 

[violetcrow]

I did this and it has worked well so far, just reassigning Perf_E boundaries in a way that those object faces which are overlapping with the region boundary are not assigned with the Perf_E condition.