Numerical Simulation of Anode Dynamic Behavior under Transverse Magnetic Field

Severe anode activity may reduce the dielectric recovery strength of the interelectrode at zero current crossing and increase the possibility of arc reignition. On the other hand, arc motion between transverse magnetic field (TMF) contacts can avoid breaking failures caused by excessive ablation. Therefore, arc motion characteristics and the thermal change process in anode region have an important influence on the successful breaking of TMF contacts. In order to study the change process of anode activity during arc motion, based on the principle of conservation, an anode dynamic behavior model considering the deformation of anode surface under the action of TMF was established in this paper. In addition, heat transfer between arc and anode, movement of molten pool, deformation of free contact surface, and the complex physical processes in which the three were coupled to each other were involved in the model. The coexistence of gas, liquid and solid was considered in the model, and the fluid volume function was used to describe the anode surface morphology. Through the established model, the thermal variation of the anode region and the deformation of anode surface with development of arc motion were analyzed.