Numerical investigation on enhancement of oxygen transfer by forced convection in liquid lead–bismuth eutectic system

Lead–bismuth eutectic (LBE) technology is being developed as a primary candidate for a nuclear coolant in accelerator-driven systems and advanced reactors. However, the corrosion of containment and structural materials remains a major issue. Properly controlling the low oxygen level in LBE to mitigate corrosion proves effective under certain conditions. To mix the oxygen uniformly and quickly, the forced convection is proposed to enhance the oxygen transport with using cover gas scheme. A lattice Boltzmman simulation of LBE flow and oxygen transport in a simplified container was carried out to explore characteristics of the oxygen transport. The oxygen control technique with cover gas scheme is formulated. To find more efficiency way to mix the oxygen, three different forced convection flow patterns on the oxygen transport are investigated. The simulation results show that the force convections induced by all the boundary conditions greatly enhance the oxygen transport in the liquid metal of our system. Both of transient oxygen distribution, oxygen diffusion time, and average Sherwood number at the interface are investigated and some useful information are also provided to calibrate low concentration level oxygen sensors.