About the SLOTH project

Project summary

Phase-field methods represent a versatile and effective approach to modelling the spatiotemporal evolution of complex physical systems that exhibit significant heterogeneities, such as phase transitions, coalescence, and cracking. These methods have found extensive application in the field of materials science, including in the modelling of the behaviour of nuclear fuels.

The phase-field approach has also been employed in recent studies conducted with the multiphysics computational tools of the PLEIADES platform¹. Broadly speaking, the PLEIADES/Fuel Performance Codes² aim at providing a state-of-the-art multiphysics multiscale description of the fuel under irradiated conditions. The inclusion of an advanced multiphysics and multiscale modelling such as phase-field, is a logical step forward. Consequently, the CEA is developing SLOTH, a multiphase-field multicomponent framework, dedicated to the study of fuel behaviour at different scales of description, from nominal operating conditions to severe accident conditions.

PLEIADES/SLOTH is developed at CEA under LPGL license (Version 3). It is based on the the MFEM Finite Element library³, which already includes the main features to have a robust, flexible and massively parallel implementation of the solution algorithms.

[Incipient melting in a pellet fragment under an ad-hoc temperature dependent enthalpy of melting](https://github.com/Collab4Sloth/Gallery)

[Polycristalline microstructure with 30 grains](https://github.com/Collab4Sloth/Gallery)

[Spinodal decomposition](https://github.com/Collab4Sloth/Gallery)

Contributors

• Development Team

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  • Clément Introïni
  • Raphaël Prat

• Living Deep Neural Network

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  • Romain Le Tellier
  • Tommaso Barani
  • Mathis Plapp
  • Isabelle Ramière
  • Luca Messina
  • Jérôme Sercombe

• Students Team

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  • Alessandro Scapini (PhD 2024-2027)
  • Clément Plumecocq (PhD 2023-2026)
  • Victor Navarre (Master 2025)
  • Jules Czuckermand (Master 2025)
  • Mouad Bakhkakh (Master 2024)
  • Etienne Delobre (Master 2023)

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1. Stéphane Bernaud, Isabelle Ramière, Guillaume Latu, and Bruno Michel. Pleiades: a numerical framework dedicated to the multiphysics and multiscale nuclear fuel behavior simulation. Annals of Nuclear Energy, 205:110577, 2024. ↩

2. C Introïni, I Ramière, J Sercombe, B Michel, T Helfer, and J Fauque. Alcyone: the fuel performance code of the pleiades platform dedicated to pwr fuel rods behavior. Annals of Nuclear Energy, 207:110711, 2024. ↩

3. Robert Anderson, Julian Andrej, Andrew Barker, Jamie Bramwell, Jean-Sylvain Camier, Jakub Cerveny, Veselin Dobrev, Yohann Dudouit, Aaron Fisher, Tzanio Kolev, and others. Mfem: a modular finite element methods library. Computers & Mathematics with Applications, 81:42–74, 2021. ↩