Modeling of transient and steady state xenon behavior in the molten salt reactor experiment

In the quest for a sustainable and climate-resilient future, significant interest is found in advanced reactor technologies in recent years including the liquid-fueled molten salt reactors (MSRs). Liquid-fueled MSRs stand out due to their unique characteristics, especially the potential online removal of fission products such as xenon-135. The removal of xenon can enhance fuel utilization and make the reactor more adaptable to load-following operations. However, the development of xenon removal system for MSRs requires improved understanding of xenon behavior in liquid-fueled MSRs. In this study, a system level Simulink model for liquid-fueled MSRs is developed and then adapted to study the xenon behavior in the Molten Salt Reactor Experiment (MSRE). The steady-state and transient xenon behavior in the MSRE is simulated and compared with available data and existing models in the literature. Good agreement is found between the simulation and the experiment under the same set of model parameters. The importance of xenon transfer between the core graphite, circulating bubbles, and fuel salt is highlighted. The Simulink model can be easily extended for future development of a xenon removal system in commercial scale liquid-fueled MSRs.