Simulation Study of Transient Characteristics of Liquid Lead-Bismuth Natural Circulation Loop

Abstract To study the natural circulation capabilities of Liquid Lead Bismuth (LBE), natural circulation loops have been designed and constructed in several countries for natural circulation characterization of LBE. These loops aim to characterize LBE’ natural circulation properties. Seeking a more profound comprehension of LBE behavior during natural circulation, this research leverages a Computational Fluid Dynamics (CFD) simulation program. This program theoretically models the circulation loop, while a one-dimensional code is employed to verify the model’s accuracy. The findings reveal that the discrepancies between the two models are minimal, thereby affirming their trustworthiness. Utilizing the validated model, a deepening of the influence of loop geometric parameter, heating power, and the configuration of the pooled solid-state oxygen control device on the natural circulation flow rate within the lead-bismuth loop. Furthermore, the CFD model is instrumental in examining the thermal and hydraulic attributes of the loop under distinct operational scenarios, namely transient startup and power jump conditions. In essence, this paper integrates two robust models to explore the thermal and hydraulic nuances of the liquid lead bismuth recirculation loop. Through this exploration, the optimal geometric parameters are established and an assessment of the viability of the pool-type solid-state oxygen control device is also performed.