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All the laws, decrees and public debates relating to the energy transition, emphasizes the importance of the study of electronuclear fleet evolution scenarios. One of the reference strategies for the French electronuclear fleet evolution considers the step by step deployment of Generation IV Sodium-cooled Fast Reactors (SFR). A proper assessment of the possible transitions scenarios requires a thorough study of the different possible trajectories and its associated consequences on the entire fuel cycle.

In this framework, this Ph.D. work aims at analyzing the impact on plutonium and minor actinide dynamic management, of ASTRID-like reactor deployment scenarios, a Generation IV SFR developed by the CEA and its industrial partners. The modeling of two ASTRID-like reactor configurations, one plutonium break-even, and one burner, allow the validation of the calculation hypothesis, the quantification of associated bias and the verification of reactor safety coefficients. It was observed that the variation of initial fuel composition had a drastic impact on the system configuration. Within the framework of this research, the dynamic fuel cycle simulator CLASS, developed by the CNRS/IN2P3 and the IRSN was further modified, to meet the requirement of new dedicated complex physics models. These new developments using multidimensional and nonlinear interpolators allow modeling of the fresh fuel fabrication and irradiation while maintaining the reactor heterogeneity throughout the simulations. With these multizone models, effects of SFR deployment is studied, and potential constraints on in-cycle materials are identified by the simulation of transition scenarios, from a Pressurized Water Reactor fleet to a mixed fleet integrating SFRs. An academic analysis of the scenarios presented within the energy transition law is proposed to extend this work.