Feedback for Challenges

[ChrSoGFG]

Hi all,

While getting familiar with FESTIM, I worked through the workshop challenges and would like to report a few minor issues I encountered in the challenge statements and/or solution files. I hope this feedback is helpful for future users.

Challenge B
In the problem description it is stated:
“We will assume that the implantation follows a Gaussian distribution with a mean of 5 nm and a standard deviation of 2.1 µm.”
The standard deviation should be 2.1 nm, not 2.1 µm. This is consistent with how it is implemented in the solution file, so the issue appears to be only in the written statement.

Challenge C
The challenge statement says:
“Consider a Eurofer pipe with an outer diameter of 25 mm and inner diameter of 20 mm at a fixed temperature of 600 K.”
However, in the solution, these values are used as if they were radii rather than diameters, which leads to an inconsistency between the statement and the implementation.

Challenge D
In the solution file, the material properties are not assigned correctly. Specifically:
E_D = D_mat.pre_exp.magnitude
is used, whereas it should be:
E_D = D_mat.act_energy.magnitude
This change has a significant impact on the resulting plots.

Challenge E
I am unable to run the code that generates the mesh. The following error occurs:
'ModuleNotFoundError: No module named 'mshr''
I believe this is due to mshr no longer being supported in newer FEniCS versions.

Thanks for providing the workshop material, and I hope these notes are useful.

Best regards,

Chris