*SPRING implementation with Calculix

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Ningrich3
Posts: 12
Joined: Mon Jul 18, 2022 4:18 am

*SPRING implementation with Calculix

Post by Ningrich3 »

Hello everyone,

my objective is to simulate a plate that's supported by four springs.

I use CalculiX and manipulate the .inp file to make use of the *SPRING card.
However, in a simple sample application I run into the problem of missing nodes in the frd file, or the file missing altogether, respecitvely (.inp file attached).
The cause seems to be related to the *Element definition in line 2120 (when deleting all code related to the spring implementation I still receive above mentioned frd errors until I delete the *Element definition).
Any hint?

Thank you so much!
Attachments
inp.txt
(92.44 KiB) Downloaded 30 times
Ningrich3
Posts: 12
Joined: Mon Jul 18, 2022 4:18 am

Re: *SPRING implementation with Calculix

Post by Ningrich3 »

Since I manually added the element set ESpring of type SPRINGA (line 2124) there is an indication that the *EL FILE step cannot compile these into the .frd file along with the C3D10 type elements from the volume model, however, attempts of restricting the scope of *EL FILE to ELSET=Evolumes or ELSET=Eall did not help with the problem.
I also defined the *NODE FILE scope as NSET=Nall to exclude the manually created nodes of the springs, but without any luck either...
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inp.txt
(90.34 KiB) Downloaded 29 times
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NewJoker
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Posts: 3014
Joined: Sun Oct 11, 2020 7:49 pm

Re: *SPRING implementation with Calculix

Post by NewJoker »

Just submit this input file outside of FreeCAD (from the command line) and use GraphiX (native CalculiX GUI) for postprocessing. This way you will avoid the limitation of the FEM module in FreeCAD.
Ningrich3
Posts: 12
Joined: Mon Jul 18, 2022 4:18 am

Re: *SPRING implementation with Calculix

Post by Ningrich3 »

@NewJoker Thank you, I'll try that first.
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