Stress Result in Shells

About the development of the FEM module/workbench.

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bernd
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Re: Stress Result in Shells

Postby bernd » Wed Apr 04, 2018 5:50 am

Found it :D Here https://github.com/FreeCAD/FreeCAD/blob ... s.cpp#L449 we gone set the count of points to the count of nodes we have in our mesh, but we need to set it not to the count of point but to the highest node ID instead. This does not crash anymore but I'm not yet happy with the way I get the highest node id. https://github.com/berndhahnebach/FreeC ... 5f4d07104e

Step by step we will get there ...
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bernd
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Re: Stress Result in Shells

Postby bernd » Thu Apr 05, 2018 6:30 am

https://github.com/FreeCAD/FreeCAD/pull/1396 it does fix the crash, and vtk mesh export works. But the result pipeline still does not work if the SMESH mesh has node gaps. An error message is printed in report view.

At least FreeCAD does no longer crash :)
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bernd
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Re: Stress Result in Shells

Postby bernd » Tue Sep 25, 2018 9:16 pm

bernd wrote:
Sun Mar 25, 2018 9:13 pm
saving and reloading the file normalizes the element and node numbering of the result mesh. They start with one after reload.
thus result mesh node numbers are not equal to results anymore thus the results are wrong. I reopened issue issue #2873
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bernd
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Re: Stress Result in Shells

Postby bernd » Tue Sep 25, 2018 9:31 pm

bernd wrote:
Thu Apr 05, 2018 6:30 am
https://github.com/FreeCAD/FreeCAD/pull/1396 it does fix the crash, and vtk mesh export works. But the result pipeline still does not work if the SMESH mesh has node gaps. An error message is printed in report view.

At least FreeCAD does no longer crash :)
issue #3617
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bernd
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Re: Stress Result in Shells

Postby bernd » Mon Jan 14, 2019 8:54 pm

bernd wrote:
Tue Sep 25, 2018 9:31 pm
bernd wrote:
Thu Apr 05, 2018 6:30 am
https://github.com/FreeCAD/FreeCAD/pull/1396 it does fix the crash, and vtk mesh export works. But the result pipeline still does not work if the SMESH mesh has node gaps. An error message is printed in report view.

At least FreeCAD does no longer crash :)
issue #3617
should be fixed with git commit 1643520 testing is highly appreciated
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HarryvL
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Re: Stress Result in Shells

Postby HarryvL » Thu Jan 17, 2019 5:28 am

much better, but still some funny colorful patches (in blue):


Strip.jpg
Strip.jpg (49.6 KiB) Viewed 185 times


OS: Ubuntu 16.04.5 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.15646 (Git)
Build type: Unknown
Branch: master
Hash: fdf8fe7bc6ed671e8b7ee064000b6f00567ce795
Python version: 2.7.12
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.1.0
Locale: English/UnitedStates (en_US)
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bernd
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Re: Stress Result in Shells

Postby bernd » Thu Jan 17, 2019 7:46 am

you gone mix bugs harry ... issue #2873 and issue #3617

generate 3D resultmesh from a 2D analysis. Run analysis:

what works now ... make a vtk result object and enjoy :D

what does not yet work ... save the FreeCAD file, reload the FreeCAD file and use FreeCAD result object viewer

BTW: vtk result should work on file reload. FreeCAD result works as long as the file is not saved.

Would you confirm this?
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HarryvL
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Re: Stress Result in Shells

Postby HarryvL » Thu Jan 17, 2019 2:07 pm

bernd wrote:
Thu Jan 17, 2019 7:46 am
Would you confirm this?
Oops sorry :oops:

VTK before export:


Strip_VTK_1.jpg
Strip_VTK_1.jpg (37.65 KiB) Viewed 150 times


VTK from import:


Strip_VTK_2.jpg
Strip_VTK_2.jpg (38.36 KiB) Viewed 150 times


Great, it works !!
wmayer
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Re: Stress Result in Shells

Postby wmayer » Thu Jan 17, 2019 4:07 pm

bernd wrote:
Thu Jan 17, 2019 7:46 am
you gone mix bugs harry ... issue #2873 and issue #3617

BTW: vtk result should work on file reload. FreeCAD result works as long as the file is not saved.
The problem with reloading the the unv file is that smesh performs the function compatMesh() and thus changes all the ids. The question is whether there is a way to handle this.
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bernd
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Re: Stress Result in Shells

Postby bernd » Thu Jan 17, 2019 5:08 pm

wmayer wrote:
Thu Jan 17, 2019 4:07 pm
bernd wrote:
Thu Jan 17, 2019 7:46 am
you gone mix bugs harry ... issue #2873 and issue #3617

BTW: vtk result should work on file reload. FreeCAD result works as long as the file is not saved.
The problem with reloading the the unv file is that smesh performs the function compatMesh() and thus changes all the ids. The question is whether there is a way to handle this.
Two years ago we disscussed this with user vejmarie and decided to leave compactMesh(), but at that time the 3D mesh result from 2D analysis (which introduces node gaps in the mesh) was not possible. Thus the bug was closed and reopend a few month ago when we found this problem. The next problem is, we can not just deactivate the compactMesh() IMHO. Thus because it is possible to compile FreeCAD with external SMESH which still has compactMesh() ...

Werner do you see any solution apart from use some compactMesh() right at the beginning when we create a mesh in FreeCAD. With this the mesh is renumbered during import from frd file.

bernd