freecad elmer

Numerical methods and mathematical models of Elmer
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Qulanan
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Joined: 05 Mar 2019, 12:23
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freecad elmer

Post by Qulanan »

hi

what free cad program to use for the ELMER field-solver?
the elmer doesnt have a drawing program, i need to import from something.
this something should be able to draw 3D structures, in a forma twhich is good for the elmer
kevinarden
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Re: freecad elmer

Post by kevinarden »

Salome is the best high end pre-processor, it can export a unv file which can be converted to elmer mesh using ElmerGrid

Gmsh is used, need to also export unv file

there is an elmer module for salome on github which writes an elmermesh directly.

this post worked for me, although I had to make edits to the script for directories

Salome: Elmer-plugin available
Post by RaJa » 22 Mar 2017, 06:43

Hi,

The Elmer-plugin (incl. ElmerGrid mesh export and sif-file generator) for the Salome CAD/Mesh platform has reached Beta status. A big thanks goes to Matthias (mzenker).
It can be downloaded here: https://github.com/physici/ElmerSalomeModule

A small demo can be found here: https://youtu.be/D2-dp4UxblY

What is it good for?
The plugin mimics the ElmerGui in the context of the Salome platform. It provides the same functionality as the "Model"-menu in the ElmerGui, allowing the definition of equations, material, boundary and body properties as well as simulation related parameters like time stepping, output file, etc.
Additionally, it provides a function that allows writing the settings into a sif-file that can be used as input for the ElmerSolver. Also, the Solver can be started from Salome. Finally, a once created sif-file can be used as input for the plugin to automatically setup a simulation.

Why not using ElmerGui?
We wanted to have everything in one single tool, since Salome already offers meshing and analysis in paraview. Building an interface to the Elmer-solver was kind of consequential.

How does it work?
When in the meshing module of Salome, the Elmer functionality can be accessed via the 'Tools'-menu: Tools->Plugins->Elmer. It contains a control window that can be activated and which provides faster access to the Elmer-functions.

Limitations?
Parallel runs of a simulation are currently supported only on Windows.
Important 1: Bodies and faces that shall be used for a simulation have to have a unique name without any blanks (e.g. "Face 1" has to be "Face1). Ideally, these names are definied via the group-function of Salome. The plugin uses the 'Use Mesh Names'-options by default and ElmerGrid crops the names at the first occurence of a blank.
Important 2: The current version also supports Salome 8.2.

Bugs?
There might be some issues with configurations we have not tested. Everything else is running stable.

Status as of Aug. 2017
We have refurbished the interface to Elmer: Everything is done via the floating control window. No cumbersome interaction via the Tools-menu anymore. Additionally, you can now set whether to use Parallel- or Single-Processing - just like in the ElmerGui.
There are also ideas about a convergence plot and a better integration in Salome.

Regards,
Rainer
mark smith
Posts: 215
Joined: 26 Aug 2009, 18:20
Location: Peterborough, England

Re: freecad elmer

Post by mark smith »

hi Rainer,

I find gmsh the way to go, it can import solid geometry from CAD or you can draw directly in gmsh.
After meshing you save the file in native gmsh format, make sure you select version 2.0 , then using elmergrid convert this gmsh mesh into elmer format.

e.g. for serial processing
elmergrid 14 2 file.msh -autoclean

for parallel processing
elmergrid 14 2 file.msh -autoclean -metis N (where N is the number of processors used)

HTH regards
Mark
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