105 / 2024-04-12 15:39:35

Study on the effect of metal droplet splashing on the breaking characteristics of DC air arc

splashing droplet,air arc,DC air circuit breaker,bidirectional coupling,particle tracing

The metal droplet splashing produced in the breaking process of the contacts has an important influence on the breaking ability of the air circuit breaker. The metal droplet splashing model and the magneto-hydro-dynamics (MHD) model are established in this work to realize the bidirectionally coupled of the two, and the MHD model is improved based on the consideration of the effect of droplet splashing on the flow field. At the same time, considering the influence of magnetic field, the metal droplet trajectories under the action of different magnetic field, the temperature distribution and air flow distribution in the arc quenching chamber under the coupling action of droplet and arc, the key parameters such as flow field velocity and arc temperature in the area affected by metal droplet splashing were traced, and the influence of different magnetic field on metal droplet splashing and arc characteristics was discussed. The results show that the droplet splashing will slow down the movement of cathode arc root, resulting in more serious electrode erosion. Droplet splashing will slow down the flow field rate of the front side of the splitter and reduce the breaking performance of the circuit breaker. The strength of the magnetic field will affect the distribution of the flow field, thus changing the splashing trajectory of the metal droplet.