This internship is part of a project on modeling nuclear fuel microstructure transformation under irradiation at CEA IRESNE.

The goal of the internship is to refine the modeling of nuclear fuel microstructure evolution under irradiation, specifically targeting recrystallization at low temperatures. The work will serve as a pathway to integrate these modeling efforts into the simulation platform PLEIADES [1], developed in the hosting unit.

By contributing to the development of an engineering-sclae computational tool, the student will be able to acquire a varied range of skills by working on:

• Physical modeling: improve the representation of irradiation defect evolution, from point defects to dislocations, by integrating defect nucleation, growth, and interaction mechanisms.
• Numerical development: optimize numerical integration methods to efficiently solve the "stiff" system of coupled differential equations describing the temporal evolution of the material under irradiation.
• Thermomechanical analysis of nuclear fuel: contribute to model development in order to use it in a thermal and mechanical simulation tool for nuclear fuel in reactor.
• Validation and applications: Compare the predictions of the improved model with experimental data available under various irradiation conditions (temperature, fission rate).

This internship will contribute to the development of more robust and predictive scientific computing tools for simulating nuclear fuel performance under irradiation, in order to use them for future reactor design.

[1] https://www.cea.fr/energies/iresne/Pages/Nos%20plateformes%20de%20recherche/Comportement%20des%20combustibles.aspx