Polycrystal simulations in Code Aster

# Nicolo Grilli
# University of Bristol
# 6 Novembre 2021

# polycrystal simulation with code aster and Mfront

# singularity image is installed according to instructions here:
https://codeaster-opensource-documentation.gitlab.io/opensource-documentation/sm_install/installation_linux.html

# But download this version, which is compatible with Ubuntu 20.04:
https://www.code-aster.org/FICHIERS/singularity/salome_meca-lgpl-2021.0.0-1-20210811-scibian-9.sif

# the polycrystal input file Polycrystal.comm is generated from previous video:
https://www.youtube.com/watch?v=evNhkEcntaU&t=555s

# then different grains are added using AFFE_CARA_ELEM

# the name of the grains is found by opening salome interface
# and select the mesh module, the name of the grains will appear on the left panel

cd ~/projects/smeca2021
./salome_meca-lgpl-2021.0.0-1-20210811-scibian-9 shell
cd ~/projects/SalomeMeca2019/test_MericCailletaud/Polycrystal

# run the simulation
as_run export

# open salome interface to visualise the output file using paravis
# the state variables can be visualised
# the meaning of the state variables is given by:

mfront-query-3.2.1 --persistent-variables MericCailletaudFiniteStrainSingleCrystalViscoPlasticity.mfront

- PlasticSlip[12] (g): plastic slip
- ElasticPartOfTheDeformationGradient (Fe): elastic part of the deformation gradient
- EquivalentViscoplasticSlip[12] (p)
- BackStrain[12] (a)

The first 12 state variables are the plastic strain on the slip systems,
the 9 variable to represent the components of Fe,
12 variables for EquivalentViscoplasticSlip[12] (p)
12 variables for BackStrain[12] (a)

More details about the meaning of the variables are:
https://sourceforge.net/p/tfel/discussion/general/thread/b90ca4c169/?limit=25#40c8