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CAD import file boundary conditions

I have a 2D model I've imported from CAD that consists of many interlinked hexagons making up a larger hexagon (like a big hexagon with smaller hexagon-shaped holes throughout). I'm trying to do a steady-state diffusion simulation in COMSOL using this model, but I'm stymied when it comes to identifying boundary conditions. I go to physics---->boundary settings, but all the boundary selections are grayed out and unavailable. I thought this might be some issue with the interior boundaries, but toggling that option has no effect (all boundaries are still unavailable). I have no problem constructing a system from scratch and entering BC's. Does anyone know what might be wrong? Using COMSOL 3.5a, diffusion module.

I've tried Googling this problem til my eyes bled, but to no avail.

3 Replies Last Post Dec 5, 2012, 2:49 PM EST
Posted: 5 years ago Nov 30, 2012, 2:57 PM EST
Hi

its COMSOl that cannot for som ereason, connect the lines you import into surfaces, and then to "geomanalyze" these into true domains and boundaries.

There are the split nad combine (create surface or solid) functions in the geometry ection, probably they had a slightly different name in 3.5

--
Good luck
Ivar
Hi its COMSOl that cannot for som ereason, connect the lines you import into surfaces, and then to "geomanalyze" these into true domains and boundaries. There are the split nad combine (create surface or solid) functions in the geometry ection, probably they had a slightly different name in 3.5 -- Good luck Ivar

Posted: 5 years ago Dec 5, 2012, 12:35 PM EST
Thanks Ivar. I think your suggestions are valid, but for some reason they're not working for me. The CAD import has definitely just brought over an assembly of lines instead of shapes, which is difficult to work with. Given the complexity of the system, I'd rather not redraw it in COMSOL but will if I have to. I'm including the file to give an idea of what's going on.

Thanks!
Adam
Thanks Ivar. I think your suggestions are valid, but for some reason they're not working for me. The CAD import has definitely just brought over an assembly of lines instead of shapes, which is difficult to work with. Given the complexity of the system, I'd rather not redraw it in COMSOL but will if I have to. I'm including the file to give an idea of what's going on. Thanks! Adam


Posted: 5 years ago Dec 5, 2012, 2:49 PM EST
Hi

then it must be you rgeometry that is nota true 3D volume (or 2D surface). I'm stuck witha "blue screen" no COMSOL tonight ;) I'll might be able to take a look tomorrow
--
Good luck
Ivar
Hi then it must be you rgeometry that is nota true 3D volume (or 2D surface). I'm stuck witha "blue screen" no COMSOL tonight ;) I'll might be able to take a look tomorrow -- Good luck Ivar

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