Multi-scale and non-invasive multi-model coupling combining Iso-Geometric and Finite Element Analysis
This repository contains the code implemented during our 5th year research project at INSA Toulouse.
Modelling and simulating mechanical structures is now a very common mathematical and engineering practice, used in various domains such as aeronautics. It allows industrial engineers to study their products and mechanical behaviors without needs for physical tests that may appear very expensive. Nevertheless, modelling different scales leads to a major issue: using the finest scale in the whole mesh carries high computational cost and memory usage. Moreover, with different models and scales, we cannot modify the whole meshes and operators at each modification. That is why we present in this paper a review and implementation of the global/local non-invasive multi-model and multi-scale coupling algorithm using the industrial software Code_Aster from EDF focusing on mechanical structures. This method allows us to introduce local models, representing singularities or refined meshes, in global models without modifying them, and with no regards about their implementation. We then investigate a global-IGA/local-FEM coupling algorithm and compare results. Combining IGA and FEM gives the best out of these two methods: a better description of global and regular solutions for IGA, and a better simulation of singularities for FEM. Our results show great benefits and fully describe the mechanical behaviors of our pieces. More attention could be spent on algorithmic acceleration, non-linear coupling or non-elastic behaviors.
Code_Aster is an industrial software for mechanical structures developed by EDF. You can download it at:
https://www.code-aster.org/spip.php?rubrique7
Salome-Meca is a free software including a CAD module, Code_Aster and post-processing module. It allows to manipulate .med files, for results visualization or meshes manipulation. You can download it at :
https://www.code-aster.org/spip.php?article295
Two main test cases are implemented. An elastic and simple girder with only three elements, with two different Young modulus. An elastic curved girder with added holes and cracks.
Once Code_Aster installated, you have to:
- change path variable to your current working directory in
global.comm - create
.exportfile taking as an example the fileCasTests/PoutreCourbe/global-temp.export - in a terminal, run
bash as_run your-export-file.export
In order to visualize your results, you can use Paravis in Salome-Meca with results files resultG.med and resultL.med for global and local solutions.
In order to plot the convergence curves, do:
python3 plot-convergence.py arg1 arg2with arg1: girder [DEFAULT], toy and arg2: residue [DEFAULT], error.
arg1 allows you to choose which case you want to display, girder for the elastic curved girder or toy for the simple toy case.
arg2 allows you to choose which type of convergence you want to display, residue for the residual of forces on the interface, error for the stagnation of the displacement field.
If there is any problem, do not hesitate to open an issue or contact us: SimonTreil or paul401.
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.