FEM object types

About the development of the FEM module/workbench.

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HarryvL
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Re: FEM object types

Post by HarryvL »

Fantastic, it works:

TestMM_1.png
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TestMM_2.png
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Next I will prepare a more practical example :D

Thanks Bernd
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HarryvL
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Re: FEM object types

Post by HarryvL »

And what a pleasing result with some mesh refinement :D ...

TestMM_2b.png
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bernd
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Re: FEM object types

Post by bernd »

wow cool !

Take into account your sandwich example may not work because of a design error I made. The mesh is written with the following preference: https://github.com/berndhahnebach/FreeC ... .cpp#L1184 May be this does not write the faces for your sandwich example. I did not know about such model technicals when I did the femmixedmeshes code.
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HarryvL
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Re: FEM object types

Post by HarryvL »

In preparation for a practical application of mixed meshes I hit a speed bump with line elements:

PB_Error_Message.png
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I can't see anything wrong with element 1, but the INP file does have a few strange looking entries for *BEAM SECTION:

PB_INP_FILE.png
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This is a vertical beam, so would it have anything to do with problems reported earlier for vertical beams?

I attach the FC file for reference:

PB_1.txt
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OS: Ubuntu 16.04.4 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.13452 (Git)
Build type: None
Branch: master
Hash: 34633c144de9133c1f9aeb7da783f369cae9bfaf
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: FEM object types

Post by bernd »

problem confirmed: I will have a look, see https://forum.freecadweb.org/viewtopic.php?f=18&t=27891 It should work on rectangular sections !
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HarryvL
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Re: FEM object types

Post by HarryvL »

I tried, but it didn't. I will have another look.
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bernd
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Re: FEM object types

Post by bernd »

look at this funny eigen frequency ...


pic.JPG
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as a workaround change in inputfile the following line

Code: Select all

*Element, TYPE=B32, ELSET=Eedges
to

Code: Select all

*Element, TYPE=B32R, ELSET=Eedges
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HarryvL
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Re: FEM object types

Post by HarryvL »

That's definitely not right as the first eigen-mode :D

PS: Is this with reactungular beams?
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HarryvL
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Re: FEM object types

Post by HarryvL »

What deformation do you get by simply applying the vertical load I entered in a static analysis?
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bernd
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Re: FEM object types

Post by bernd »

It is eight or nineth frequency. I used your file:

- double click on analysis
- double click on solver
- change analydis to frequency
- write input file
- change element type to B32R in input file (see work around)
- click on run ccx
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