Xiaokang Wang, Yang Song, Xufan Wang, Fuchuan Duan, Zhigang Liu
Abstract The dynamic interaction between the pantograph and the overhead conductor rail (PC) system directly affects the current collection stability of electric locomotives. Distinct from previous work centered on transient arcing behaviour, this paper investigates the phase-change-induced melting and ablation characteristics of the rigid contact wire during a single complete PC dynamic separation process. Firstly, a multiphysics-coupled model of the PC offline arc is developed that accounts for energy transfer mechanisms during the transient arcing process, including Joule heating, thermal conduction and radiation. Subsequently, a phase-change melting model of the contact wire is established by incorporating the latent heat effects induced when the contact wire surface temperature reaches its melting point. Then, based on the dynamic simulation model, the obtained separation trajectory of the PC contact pair is applied to the numerical model to conduct a series of transient arcing simulations. Finally, the phase-change melting characteristics of the contact wire and their evolution are revealed under varying separation distances, current intensities and crosswind conditions. The results indicate that a larger separation distance leads to a greater liquid-phase area in the contact wire. Unlike the initial liquefaction time, the liquid-phase area is positively correlated with the current and negatively correlated with the crosswind speed. Additionally, compared to the PC separation process, transient arcing during the PC re-contact process induces a more pronounced thermal accumulation effect.