Research on the Multi-field Coupling Mechanisms and Quasi-steady State of Vertical Electrode Rare Earth Electrolysis Cells Using the CFD–PBM Method
摘要
Molten salt electrolysis is the mainstream process for preparing light rare earth metals and their alloys. The high-temperature and opaque reaction environment makes it difficult to conduct in situ observation, which limits the in-depth exploration of the electrolysis mechanism. To deepen the understanding of the electrolysis process and provide theoretical support for its intelligent transformation and large-scale technological upgrading, a mathematical model for the electrolysis process was developed, incorporating electric, concentration, thermal and two-phase flow fields for the vertical-insert electrode rare earth electrolytic cell, simulating from startup to quasi-steady state. The PBM–VOF coupling model was employed, to address bubble nucleation, growth, and coalescence from the sub-grid scale to the macroscopic scale. The results of the calculations carefully elucidated the energy transfer, flow dynamics, and inter-field interaction in the molten salt electrolysis process. Affected by natural convection and bubble-driven forces, the electrolyte exhibits a complex flow with a speed of approximately