How to keep an internal face using -opnbdy

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#1

Dear MMG users and developers,

Happy holiday.

I tried to use -opnbdy option to keep an internal geometric surface(marked by orange) in 3D.

Screenshot from 2024-12-26 03-48-04
Screenshot from 2024-12-26 03-48-041884×1130 82.8 KB

Then run mmg3d-O3 -opnbdy LumPort.mesh
I tried version 5.8.0 and 5.7.0.
The geometric surface can not be preserved for the final mesh. The initial mesh and solution file are attached.

Screenshot from 2024-12-26 03-50-05
Screenshot from 2024-12-26 03-50-051920×1288 607 KB

LumpPort.mesh (2.4 KB)
LumpPort.sol (206 Bytes)

How to resolve this issue ?
Thanks,

Xiaodong

#2

Hello, you need to tell mmg where the border of your internal surface is not smooth. For this you need to tag the corners nodes as “corners”.

Happy holiday

#3

Thanks a lot, Felipe. Happy holiday.