Numerical Simulation of Dynamic Behavior of Vacuum Anode Melt Pool Based on Level-Set Approach

During the interruption process of vacuum circuit breakers, the anode contacts undergo ablation due to the high-energy heat flux from the vacuum arc, resulting in melting, evaporation, and splattering. This increases the metal vapor density in the arc region, thereby raising the probability of dielectric breakdown and interrupting failure. To address the limitations of conventional methods in capturing dynamic gas–liquid interfaces and molten pool flow, a multiphysics model coupling heat transfer, phase change, and fluid flow was developed using the Level-Set method. The model was employed to investigate anode erosion under vacuum arc conditions, with comparative analysis of temperature distribution, evolution of pool morphology, and evaporation rates under different arc currents. Results demonstrate that volumetric forces drive radial flow of the molten metal, modifying the pool geometry and promoting temperature uniformity within the liquid region. This study clarifies the formation mechanism of the anode molten pool, offering valuable insights for optimizing contact materials and improving structural design.