After a steam generator tube rupture (SGTR) accident occurs in a lead-bismuth eutectic (LBE) alloy-cooled reactor, supercooled water on the secondary side is injected into the high-temperature molten LBE on the primary side. Possible consequences arising from SGTR include LBE solidification, damage to the reactor components caused by pressure waves, and unexpected reactivity owing to steam migration into the reactor core.

This study aims to conduct a computational fluid dynamics pre-computation for the LBE alloy-cooled reactor to clarify the phenomena and determine the working conditions of LBE-water interaction.

Firstly, a large experimental platform for the LBE-water interaction was set up by the Innovative Nuclear System Laboratory in Shanghai Jiao Tong University. Then, the physical process of of LBE-water interaction was described on the basis of Fluent, coupling VOF model, Lee model, and SST k-ω model, and the numerical methodology with existing experimental data was validated. Thereafter a two-dimensional model of the experimental facility was established using ANSYS Fluent. Finally, multi-case simulations were conducted to simulate the overall process of the experiment and examine the effects of water inlet velocity, water inlet temperature, and initial LBE temperature.

The simulation results indicate that the jetting process can be divided into three stages and LBE solidification is avoided under the designed conditions. The minimum LBE temperature decreases with lower water inlet temperatures or higher inlet velocities. Concurrently, the maximum void penetration depth increases with elevated water inlet temperatures and velocities.

The results of this study provide a valuable reference for future experimental studies.