Surface meshing problem

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furki1234
Posts: 7
Joined: Thu Sep 16, 2021 2:54 pm

Surface meshing problem

Post by furki1234 »

Hi!
My model is deck and also surface from space claim with share topology and I have tried to modal analysis in freecad.
But while meshing with Netgen my surface meshes is independent so ı even can not handle solution due to the mesh fail.
so how can ı mesh whole model with surface mesh and with together?



OS: Ubuntu 20.04.2 LTS (ubuntu:GNOME/ubuntu)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24291 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 0.19.2)
Hash: 7b5e18a0759de778b74d3a5c17eba9cb815035ac
Python version: 3.8.8
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chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Surface meshing problem

Post by chrisb »

Moved to FEM forum.
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bernd
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Location: Zürich, Switzerland

Re: Surface meshing problem

Post by bernd »

very difficault to guess without a file? Would you post a file which shows the problem
furki1234
Posts: 7
Joined: Thu Sep 16, 2021 2:54 pm

Re: Surface meshing problem

Post by furki1234 »

bernd wrote: Fri Sep 17, 2021 4:57 am very difficault to guess without a file? Would you post a file which shows the problem
Hi,
From space claim file export to freecad with iges file type all surfaces.neither meshed correctly nor handle solution.
And also ı have tried export step file to freecad but same error.All calculix results 0.
I can solve with solid geometry for same geometry.But surface, ı could not.

Thanks for eveything.
Attachments
all results is zero
all results is zero
Ekran görüntüsü 2021-09-17 11-30-22.png (449.78 KiB) Viewed 1099 times
independet mesh view
independet mesh view
Ekran görüntüsü 2021-09-17 10-58-55.png (423.3 KiB) Viewed 1099 times
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bernd
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Location: Zürich, Switzerland

Re: Surface meshing problem

Post by bernd »

same again with picture we could only guess. You wuld need to give us the date to test with ...
NewJoker
Posts: 171
Joined: Sun Oct 11, 2020 7:49 pm

Re: Surface meshing problem

Post by NewJoker »

So the mesh was generated correctly after all (since you already have the results).

Try clicking on CCX_Mode_Results, it should show you the eigenfrequency and then you can double click it to see displacements (just keep in mind that those aren’t the physical values).
furki1234
Posts: 7
Joined: Thu Sep 16, 2021 2:54 pm

Re: Surface meshing problem

Post by furki1234 »

bernd wrote: Fri Sep 17, 2021 10:49 am same again with picture we could only guess. You wuld need to give us the date to test with ...
Here it is my model file.

https://drive.google.com/drive/folders/ ... sp=sharing
NewJoker
Posts: 171
Joined: Sun Oct 11, 2020 7:49 pm

Re: Surface meshing problem

Post by NewJoker »

You should rebuild the model for the analysis, it has some intersecting surfaces that can't be meshed properly:

model.JPG
model.JPG (92.44 KiB) Viewed 869 times
furki1234
Posts: 7
Joined: Thu Sep 16, 2021 2:54 pm

Re: Surface meshing problem

Post by furki1234 »

NewJoker wrote: Fri Sep 17, 2021 4:19 pm You should rebuild the model for the analysis, it has some intersecting surfaces that can't be meshed properly:

The main problem is actually exporting surface. While exporting the model -my model is the only surface- which file format is the best suited and intersect correctly?
I have more complicated geometry so ı could not make a model in freecad.I have to export another modeler.
model.JPG
NewJoker
Posts: 171
Joined: Sun Oct 11, 2020 7:49 pm

Re: Surface meshing problem

Post by NewJoker »

I don't think it's because of the export format, standard STEP should work fine in all cases. Most likely the problem lies in the way the surfaces were modeled in this external software.
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