As an important way to explore the ablation of vacuum switch electrodes, simulation of vacuum arc characteristics has become a hit in its field. A two-dimensional magneto-hydrodynamic model was established to simulate vacuum arc in this paper. The electrode radius and the gap distance were set to 25mm and 10mm, respectively, and boundary conditions were set according to experimental data of previous researchers. The simulation results shown that: 1) A 10kA vacuum arc plasma flow is in subsonic state, and the maximum pressure appears in the center of cathode. 2) As plasma flows from cathode to anode, ion temperature and electron temperature increase, and their maximum temperature reach 7.2 eV and 7.4 eV, respectively. 3) the maximum energy flux density reaches 220MW/m² on anode surface, and electron energy flow density occupies the main part. The results are basically consistent with the relevant experimental and calculation results of other researchers.

vacuum arc,energy flux density,magnetohydrodynamic model