Development of a Computational Framework for Multiphysics Multiphase Species Tracking using NEAMS Tools

Program Document · Fri Aug 30 04:00:00 EDT 2024

OSTI ID:2476503

Tano Retamales, Mauricio Eduardo ^[1]; Walker, Samuel Austin ^[1]; Abou Jaoude, Abdalla ^[1]

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1. Idaho National Laboratory

This report implements a high-fidelity multiphysics modeling framework using the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program tools to track isotopic species in Molten Salt Reactors (MSRs), with a specific focus on the 91-depletion chain within the Molten Salt Reactor Experiment (MSRE). The model integrates neutronics, thermal-hydraulics, depletion, and thermochemistry to simulate the production, transport, and phase transitions of isotopes under steady-state and transient conditions. The main findings reveal that isotopes such as bromine-91 largely remain in the liquid phase, while others, including krypton-91and yttrium-91, transition to the gas phase, significantly influencing the reactor’s radiological source term. The study also shows that during transients, like a reactivity insertion transient, rapid void formation and the expansion of the liquid-gas interface led to substantial transfers of dissolved isotopes into the gas phase, altering isotope distribution and largely increasing the source term in the off-gas system. Additionally, the research highlights that short-lived isotopes dominate the initial off-gas response during transients, while longer-lived isotopes determine the equilibrium state, underscoring the necessity of dynamic simulations for accurate species tracking and reactor safety analysis. The developed methodology will be applied in the future to the tracking of a larger number of species and introduce other species tracking mechanisms, such as deposition and plating.

• Research Organization: Idaho National Laboratory (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: 58
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 2476503
• Report Number(s): INL/RPT-24-80404-Rev000
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
97 MATHEMATICS AND COMPUTING
99 GENERAL AND MISCELLANEOUS
Computational Framework for Multiphysics Multiphase Species Tracking using NEAMS Tools
NEAMS Tools