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Mesh of very thin geometries
Posted May 14, 2014, 9:29 p.m. EDT Mesh Version 4.3b 7 Replies
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I would like to study in a very thin geometry. It is basically a disk (diameter 5mm, thickness 1um) with 4 rectangular channels (width 1mm, thickness 1um). I understand that cannot use the automatic mesh for this geometry because of the large aspect ratio (~ 1000).
I have been reading other posts on this forum and I understand that I should use a Swept Mesh. I can easily do it for just a thin disk where source face and destination face are the two opposite faces of the disk. Unfortunately, I have a problem when I try with my geometry (disk and 4 channels). It works for the channels but It gives me the following error on the lateral face of the disk:
"Unsupported topology of linking face."
In order to work on the mesh, I have volontarly increase the thickness (disk and channels) to 1mm. Screenshots of the geometry and the error message are attached. I couldn't attache the .mph file because its size is too large (10M).
Could you help me with that problem?
Thanks
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How about this? I made a work plane where I drew the shape, made a union, keeping interior boundaries, and extruded it 1 µm. Now swept mesh is no problem.
Attached a screen shot and the model file. Wish you have 4.4 so you could open it.
BR
Lasse
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Thank Lasse for your help. I don't have 4.4 yet but I will get it soon. I can see that it works well from your screenshot. However, I should have been more precise in the description because it turns out that the 4 channels are not (1mm x 1um) but (1mm x 0.5 um). The other thing is that 2 opposite channels must be extruded from the bottom plane and the 2 other channels from the top plane.
With this geometry, the disk has a different face on the bottom plane than on the top. To make a test I have just draw 1 disk and 2 channels using work planes. Then, I have used "form a composite domain" for the disk and the piece of channel inside the disk. I have tried to mesh the disk (see screen shot attached) but it does not work.
Do you have any idea how I could solve this problem?
Thanks a lot.
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I tried several things but was not able to find a solution. I wish somebody from Comsol support would reply this.
Lasse
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If your license is eligible for support from COMSOL, feel free to contact our support team through support@comsol.com for assistance with this question.
Best,
Jeff
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Our COMSOL licence is provided by CMC Microsystems and I could not register it on COMSOL website. Do you know if it is possible to do it?
Thanks,
Xavier
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Modeling a membrane 2µm thick over a suspended structure 20µm thick with different geometry for a MEMS application.
Thank you in advance for any help.