Friday, December 13, 2013

Finite Element Analysis (FEA): CalculiX

Good morning,

I wanted to share a great piece of software for Finite Element Analysis, which usually refers to structural solvers. I am using it to verify whether certain structures subjected to certain loads safely operate within displacement and yield stress criterion. I am using it for a prototype of an invention of mine, which I am excited to finally be close to building. This prototype is a result of CFD and FEA analysis. Anyway, the website for CalculiX provides all of the software and helpful installation guides and tutorials.

I also wanted to share a troubleshooting tip for the CalculiX CrunchiX (CCX). Calculix has two components: the GUI and the solver. These are named CalculiX GraphiX (CGX) and CalculiX CrunchiX (CCX). I was getting the following error when trying to use the already-compiled provided CCX executable on the CalculiX website:

ccx: error while loading shared libraries: libgfortran.so.2: cannot open shared object file: No such file or directory

I did not have libgfortran.so.2, but I did have libgfortran.so.3. I verified this by:

locate libgfortran.so.3

Using the directory location output from the above command, I linked the .so.3 to .so.2 by:

sudo   ln   -s   /usr/lib/x86_64-linux-gnu/libgfortran.so.3   /usr/lib/libgfortran.so.2

And then my executable no longer had the aforementioned error...

HOWEVER, I kept getting other errors. I could do one of two things... Try to install the package that had libgfortran.so.2, or compile CalculiX from source. Since the package containing libgfortran.so.2 is deemed obsolete by the Ubuntu developers, I could not find and install it easily. So, I decided to compile CalculiX from source, and I successfully did so. I will create another post for details.

5 comments:

  1. say, do you happen to know if it is possible to perform 2D thermal analysis with calculix?

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    Replies
    1. I was not aware of that, but after a quick Google search it appears it is. You can find information on the Calculix website.

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  2. Thank you very much for a quick reply.

    I was hoping for a more specific answer :-(

    I have done some Google searches and read the User's manual and, no, I myself have not been able to find a way to do 2d thermal analysis...for example...what precisely would be the element type for such an analysis? If I only knew that, I might be able to go from there.

    thanks again

    regards

    gsal

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    Replies
    1. Here is a helpful tutorial: https://www.youtube.com/watch?v=om-IK2RVXhE. At 3 minutes in, he specifies the heat transfer parameters. Good luck!

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    2. ...it looks like I finally found it...shell elements S3, S4, S6, S8 can be used (with minimal thickness) to achieve a 2D thermal analysis.

      thanks.

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