自由燃烧电弧的磁流体动力学数值模拟

摘要

In this work, the Magneto-Hydrodynamic (MHD) model based on the magnetic vector potential description is used to simulate a DC argon free-burning plasma arc. The temperature and velocity fields of the arc are obtained by solving the electromagnetic equations and hydrodynamic equations with the coupled iterative computation. The simulation results that clearly show the phenomenon of high temperature cathode jet of plasma-arc are compared with the other research results. The effect of the cathode sheath to the simulation results is analyzed specially in this paper. For the argon free-burning arc, the characteristics of plasma arc flow and heat transfer under different arc current conditons have been obtained, which provides some useful knowledge for industrial applications of arc plasma.%采用基于磁矢量势描述的磁流体动力学模型对直流氩气等离子体自由燃烧电弧进行了数值模拟研究.通过对电磁场方程组和流体力学方程组的耦合迭代计算,求解得到了电弧温度场和速度场等重要结果.计算结果清晰反映出等离子体电弧的高温阴极射流现象,并与国际同行的实验和数值结果相互对照.还特别分析了在考虑电极鞘层时对电弧模拟结果的影响.得到了不同电流下氩气等离子体电弧流动和传热状态变化规律,有助于在电弧工业应用中进行热分析和电功率控制.