New article published in 12(4B) - ENFIR/INAC 2024

Thermohydraulic Performance in SMR Reactors with Mixed Oxide (U, Th)O2 Fuel: A Computational Approach

Abstract: This paper presents a computational study on the thermohydraulic performance of subchannels within Small Modular Reactor (SMR) configurations using Mixed Oxide (MOX) fuels comprising (U, Th)O₂ alongside subchannels containing conventional UO₂. The research aims to evaluate these fuel types operational efficiency and safety within the context of small-scale reactors. Utilizing a Computational Fluid Dynamics (CFD) model implemented in OpenFOAM, this study considers the variability of the thermophysical properties of the materials as influenced by temperature changes. The findings reveal that MOX fuels exhibit lower maximum temperatures than UO₂, suggesting a more uniform radial temperature distribution. Moreover, both the cladding and coolant temperatures remain within safe operational limits across all scenarios examined, highlighting the potential of MOX fuels to enhance the safety and efficiency of SMRs. This analysis advances our understanding of the thermal behavior of advanced fuel compositions in nuclear reactors. It underscores the importance of comprehensive thermohydraulic studies in the design and operation of next-generation nuclear power systems. Read full article.

Neutronic study of ELECTRA using reprocessed fuel and depleted uranium

Astract: The present work simulates the European Lead Cooled Training Reactor (ELECTRA), focusing on studying the neutronic parameters of a small fast nuclear reactor. The goal is to evaluate the possibility of incinerating minor actinides and the potential for energy production from ²³⁸U. The simulations consider the following scenarios: depleted uranium mixed with the reprocessed fuel, and individual fuel rods containing only depleted uranium positioned at different locations within the reactor core. The results show that the use of reprocessed fuels could contribute to the reduction of minor actinides, while the use of depleted uranium reduces reactor criticality by acting as a neutron absorber. Most uranium nuclides do not undergo fission during burnup, which increases their isotopic concentration. Read full article.