An investigation of arc root motion by dynamic tracing method

In this paper, an investigation of arc root behavior on a pair of parallel electrodes is presented. An effective filtering method is introduced to allow the clear observation of arc root behavior. The position of the arc root is identified and tracked by a multi-objective dynamic tracing algorithm. Thus the trajectories and the speeds of arc roots can be obtained. The results show that the movement of the cathode arc root is generally continuous while that of anode arc root has a jumping pattern. However, we find the jumping events of cathode root in a certain case, and we show that the anode arc root can strongly affect the motion of cathode arc root. We also illustrate that the bent arc jet, the high melting point material and the low work function of cathode can promote the rapid movement of the arc root.