数值仿真HPM大气击穿中等离子体丝状阵列的形成

Numerical Simulation of Filamentary Plasma Array Formation in Microwave Breakdown

文章结合Maxwell方程,修正的自洽电子流体方程,采用时域有限差分法(FDTD)对高功率微波(HPM)大气击穿进行了仿真,分析了等离子体丝状形成过程、原因,结果表明:气体击穿后,形成沿着波的传播方向规律的排列着的等离子体丝状,离散的丝状向源的方向发展,相邻等离子体丝状之间的距离略小于1/4波长,等离子体丝状向源方向发展是电离和扩散共同的结果。

The simulation of high-power microwave breakdown of atmosphere is made by Finite Difference Time Domain method （FDTD） in relation to Maxwell equation and the electron fluid mod- el. The reason and the process of the formation of plasma arrays have been analysed. The results show the evolution of the plasma filaments spaced less than one-quarter wavelength, the sequential discrete filaments propagating back toward the source, and plasma array formation due to the combination of ionization and diffusion.