2024/11/06 by Mathis Caprais, Caprais, Mathis, A. Bergeron +1
Engineering · Physics and Astronomy · #Atomic and Subatomic Physics Research #Computational Physics (physics.comp-ph) #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Nuclear Physics and Applications #Nuclear reactor physics and engineering
paper · pdf · doi:10.48550/arxiv.2411.03788
openalex publication_date 2024/11/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this study, the Method of Characteristics (MOC) for Delayed Neutron Precursors (DNPs) is used to solve the precursors balance equation with turbulent diffusion. The diffusivity of DNPs, significantly higher than molecular diffusivity, emerges in turbulent flows from the time-averaging of the DNPs mass balance equation. To integrate this effect within the MOC framework, the advection-reaction component of the DNPs balance equation is solved using the MOC, while the diffusive source is computed from the concentration of the previous iteration. The method is validated on a 2D recirculating pipe reactor with high Reynolds number flow, comparing the MOC with diffusion to a standard finite volume (FV) discretization of the fission products balance equation. Additionally, the impact of the diffusivity term on DNP distributions and reactor reactivity is quantified as a function of the turbulent Schmidt number.