[Fixed] brick20 (hexa20) mesh gives other results than tet10

About the development of the FEM module/workbench.

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bernd
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Re: brick20 mesh gives other results than tet10

Postby bernd » Sun Mar 01, 2020 9:14 pm

magnitude: 87.55 mm
max z: -87.17 mm
:D

OS: Debian GNU/Linux 10 (buster) (KDE//usr/share/xsessions/plasma)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.19766 (Git)
Build type: Unknown
Branch: master
Hash: 2d6aa10b69f9d2c9a37ba08f33cbc5b528c2b020
Python version: 3.7.3
Qt version: 5.11.3
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: German/Switzerland (de_CH)


canti_brick20.FCStd
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bernd
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Re: brick20 mesh gives other results than tet10

Postby bernd » Sun Mar 01, 2020 10:12 pm

git commit eeb97b36 adds this example to the code and git commit 3f399736 makes a unit test ...

to run the example from Python directly use:

Code: Select all

from femexamples import ccx_cantilever_std as canti
canti.setup_cantileverhexa20faceload()
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ebrahim raeyat
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Re: brick20 mesh gives other results than tet10

Postby ebrahim raeyat » Sun Mar 01, 2020 10:57 pm

bernd wrote:
Sun Mar 01, 2020 9:14 pm
magnitude: 87.55 mm
max z: -87.17 mm
in opensees i gives this result:

-87.1642 mm!!
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bernd
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Re: [Fixed] brick20 (hexa20) mesh gives other results than tet10

Postby bernd » Sun Mar 01, 2020 11:22 pm

exact deformation in ccx on node 5

Code: Select all

8.13413E+00 1.73873E-03 -8.71642E+01
means -87.1642 mm too. This makes sense if the same mesh and element type is used the same (exact the same) deflection. For tetra10 element and z88 and calculix it is the same, exact the same deflection.

:D
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ebrahim raeyat
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Re: [Fixed] brick20 (hexa20) mesh gives other results than tet10

Postby ebrahim raeyat » Sun Mar 01, 2020 11:42 pm

bernd wrote:
Sun Mar 01, 2020 11:22 pm
exact deformation in ccx on node 5

Code: Select all

8.13413E+00 1.73873E-03 -8.71642E+01
means -87.1642 mm too. This makes sense if the same mesh and element type is used the same (exact the same) deflection. For tetra10 element and z88 and calculix it is the same, exact the same deflection.

:D
in opensees node 5:

Code: Select all

8.13413 0.00173873 -87.1642
Example8.1.py
(1.58 KiB) Downloaded 4 times
nodes.py
(7.69 KiB) Downloaded 4 times
element.py
(3.78 KiB) Downloaded 3 times
load.py
(731 Bytes) Downloaded 4 times
i could not load .tcl file, thus i renamed those to .py file! i will soon upload python file.
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bernd
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Re: [Fixed] brick20 (hexa20) mesh gives other results than tet10

Postby bernd » Mon Mar 02, 2020 9:25 am

we should move all opensees related posts in the opensees topic.


EDIT: ahh you did already. OK than any disscussion in this regard will continue there ... see https://forum.freecadweb.org/viewtopic. ... 70#p373327