摘要详情

ID / 提交时间

73 / 2024-04-10 14:47:59

标题

Study on arc root stagnation phenomenon and erosion characteristics of contact edge during DC air interruption

关键字

arc root stagnation, improved level-set method, contact erosion, DC interruption

主题及专题

7)Fundamental physics in Switchgear

状态

摘要录用

作者

Wei Duan / Shenyang University of Technology

Jing Li / Shenyang University of Technology

Juncheng Yang / Shenyang University of Technology

Shuxin Liu / Shenyang University of Technology

Yundong Cao / Shenyang University of Technology

摘要

Arc erosion of the contact is a major threat to the life of the apparatus and the stability of interruption. The arc erosion characteristics under conditions of contact edge stagnation differ significantly from those under normal arc duration conditions. a DC arc interruption test platform is established in this paper to investigate the phenomena of contact edge arc stagnation and the mechanism of contact erosion during DC interruption through experiment and simulation. The analysis included an examination of arc motion and contact morphology, and the accuracy of the simulation model was validated. A magnetohydrodynamic (MHD) model considering energy transfer between the arc and the contact was developed for simulation, and on this basis, the surface tension, recoil pressure, Marangoni effect, and shear stress caused by metal vapor flow were coupled in an improved level-set method to track the free interface and a two-dimensional transient model of air arc contact erosion and splashing was established. A comprehensive analysis was conducted on heat transfer, mass transfer, and fluid flow during the process of arc stagnation at the contact edge. The results indicate that the arc stagnation process causes erosion at the contact edge, resulting in the formation of a molten pool or even splashing. Vortices beneath the moving contact dissipate energy from the anode arc root, providing vortex lifting force to accelerate the arc root transition. Increasing the magnetic induction intensity and interruption speed reduces the stagnation time and alleviates the degree of contact erosion during the arc stagnation-transition process at the contact edge. However, when interruption speeds more than 5 m/s and magnetic fields more than 50 mT, the enhancement effect is marginal, and erosion worsens progressively when magnetic fields more than 50 mT.