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Issue with fillet
Posted 2024年2月13日 GMT-5 07:49 11 Replies
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Hello guys. I am Electronics Engineering student in Politecnico di Milano and I am using Comsol for my thesis project. I have an issue with the fillet, in particular I'm able to built it in the geometry butn when I form the union, it becomes a straight line. I cannot increase the radius of the fillet as the structure is in the order of few um. Is it possible to change the grid of the points used by Comsol to build the union? Does anyone have the same issue? Thank you so much, Raffaella
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Have you tried a different tolerance?
-------------------René Christensen, PhD
Acculution ApS
www.acculution.com
info@acculution.com
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Raffaella,
I am not sure if this is the issue, but you could try to change the geometry units to µm instead of m.
Cheers Edgar
-------------------Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
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Have you tried a different tolerance? Hello René, yes I tried to change the absolute tolerance from nm to fm but nothing changes.
Thanks Raffaella
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Raffaella,
I am not sure if this is the issue, but you could try to change the geometry units to µm instead of m.
Cheers Edgar
Hello Edgar, I tried to change it too, but nothing works. It seems a sort of resolution problem depending on the dimension of the element that Comsol accepts as the lowest possible. In fact, if I modify the radius putting it equal to 300 nm, I see a sort of fillet (see my attatched screenshots).
Thanks, Raffaella
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I suggest you upload the model, so we can play with it.
-------------------Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
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Hi Raffaella,
This is a visualization artifact. Go to the Mesh settings and set a small Maximum element size on the fillet edge. Then you will get a mesh that shows the true fillet arc.
Best regards,
Magnus
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I suggest you upload the model, so we can play with it.
Hello Edgar, here uploaded my projest with the fillet built. When you form the union, you can see that the fillet change structure. Thanks a lot for your haelp. Raffaella
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Hi Raffaella,
This is a visualization artifact. Go to the Mesh settings and set a small Maximum element size on the fillet edge. Then you will get a mesh that shows the true fillet arc.
Best regards,
Magnus
Hello Magnus, thanks for the suggestion. I put as max element size 1e-9 m and min size of 0.5e-9 m. But the problem occurs before defing the mesh, when we form the union of the geometry. Kind regards, Raffaella
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Raffaella,
as Magnus pointed out it is a visualization effect in the geometry, probably because you have very large ratio in the dimensions of the thing.
Use an edge mesh for the fillet at the top of the meshing sequence, that properly resolves the curvature.
This way the curvature will be accounted for in the calculation and it will be shown in the result plots. The artifact will remain in the geometry visualization, but you can ignore it. Of course it would be nice if the geometry visualization avoided such artifacts that can create confusion (pinging COMSOL).
Cheers, Edgar
-------------------Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
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Raffaella,
as Magnus pointed out it is a visualization effect in the geometry, probably because you have very large ratio in the dimensions of the thing.
Use an edge mesh for the fillet at the top of the meshing sequence, that properly resolves the curvature.
This way the curvature will be accounted for in the calculation and it will be shown in the result plots. The artifact will remain in the geometry visualization, but you can ignore it. Of course it would be nice if the geometry visualization avoided such artifacts that can create confusion (pinging COMSOL).
Cheers, Edgar
Hello Edgar, thanks for your advise. Now I'm able to see the mesh on the fillet too. Thank you so much and have a nice day! Raffaella
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Raffaella,
as Magnus pointed out it is a visualization effect in the geometry, probably because you have very large ratio in the dimensions of the thing.
Use an edge mesh for the fillet at the top of the meshing sequence, that properly resolves the curvature.
This way the curvature will be accounted for in the calculation and it will be shown in the result plots. The artifact will remain in the geometry visualization, but you can ignore it. Of course it would be nice if the geometry visualization avoided such artifacts that can create confusion (pinging COMSOL).
Cheers, Edgar
Hi Edgar,
Such an improvement is on our radar.
Best regards, Magnus
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