FEM Instructions

About the development of the FEM module/workbench.

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dubstar-04
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FEM Instructions

Post by dubstar-04 »

I have been playing with the FEM workbench machine details here:

OS: Windows
Word size: 64-bit
Version: 0.14.3692 (Git)
Branch: releases/FreeCAD-0-14
Hash: 5fe6e0c48f621f1136595e47cc8d7346090e7456
Python version: 2.7.6
Qt version: 4.8.5
Coin version: 4.0.0a
SoQt version: 1.6.0a
OCC version: 6.6.0


I can successfully create an analysis, mesh the object and add a material, however whenever i try to add a node set i can't select any nodes to add to it, i have tried volume and surface and neither seem to work.

should this work on windows?

Thanks,

Dan
jmaustpc
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Re: FEM Instructions

Post by jmaustpc »

Hi Dan

I don't know the answer however if it is any help this is what Juergen said about FEM in general...

viewtopic.php?f=18&t=6963#p56362

Jim
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dubstar-04
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Re: FEM Instructions

Post by dubstar-04 »

it works fine until i need to select a nodeset.

I am wondering if this is a bug in the release version.

Image
ickby
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Re: FEM Instructions

Post by ickby »

For what do you need the node set? I'm also unable to create one, but to do some calculations currently you don't need it. If you want to set constraints you must hide the mesh and use the part. When you create constraints or loads you can use the "select reference" button in the task view and then select faces or edges of the normal part, not the mesh.

Maybe that helps.
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dubstar-04
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Re: FEM Instructions

Post by dubstar-04 »

ickby,

thanks for the reply. its not obvious that the boundary conditions need to be applied to the original part.

Image

thanks,

Dan
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NormandC
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Re: FEM Instructions

Post by NormandC »

Am I to understand this only works on Windows?

What would be required for this to work on Linux, specifically on both the Ubuntu Stable Releases and Daily Builds PPAs?

I've read topics about netgen and smesh and calculix and I am totally lost. I have no use for FEM but I'm sure other Lunix users would like to get the same functionality as Windows users...

Sorry for hijacking the topic, let me know if you want me to split this into a separate topic.
ickby
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Re: FEM Instructions

Post by ickby »

In general on linux freecad would need to be compiled with FREECAD_BUIL_FEM_NETGEN=1 . This then requires to have netgen's nglib available AND netgen needs to be compiled with the same occ version freecad is compiled with. So if this is to be enabled on the ppa netgen needs to be compiled with the ppa occ version.
Then calculix needs to be made available through a ppa. And then someone has to adopt some of the python code which runs calculix.
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Re: FEM Instructions

Post by NormandC »

Thanks. Some work required then, not a quick fix.
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quick61
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Re: FEM Instructions

Post by quick61 »

normandc wrote:Thanks. Some work required then, not a quick fix.
I'd say more than a little. With my continuing fight, trying to get Netgen to build with OCE 6.7.1, I'm feeling compelled to rename Netgen "Moby-Dick", as I find my self quoting the line "to the last I grapple with thee..." So some work on Netgen is also needed with OCE 6.7.1 release coming up quick. I don't know how active the maintainers of Netgen are and how quick they will be in fixing their code to build with the latest OCE.
This post made with 0.0% Micro$oft products - GOT LINUX?
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kwahoo
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Re: FEM Instructions

Post by kwahoo »

FreeCAD is compiling with Netgen from Ubuntu 14.04 repository for me. I can mesh shapes and add constraints without errors. The biggest problem is Calculix installation. Paths need some tuning, inside MechanicalAnalysis.py you can see Windows-specific stuff:

Code: Select all

        self.CalculixBinary = FreeCAD.getHomePath() +'bin/ccx.exe'
edit:
Image

OS: Ubuntu 14.04 LTS
Word size: 64-bit
Version: 0.14.3698 (Git)
Branch: master
Hash: 8188bd5385aa0f1e3c93d90613750c7dfc562b33
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
SoQt version: 1.6.0a
OCC version: 6.7.0
Last edited by kwahoo on Sun Jul 13, 2014 6:02 pm, edited 1 time in total.
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