初始种子电子团对短空气间隙流注放电行为的影响

Influence of Initial Seed Electron Cluster on Streamer Discharge in Short Air Gap

流注放电过程中初始种子电子团的形成数量及位置具有随机性,为揭示初始种子电子团对流注放电行为的影响,建立流体动力学-化学反应混合模型,数值仿真大气压下棒-板间隙为5 mm的流注放电过程。模型包括电子、正负离子连续性方程、电子平均能量方程和电场的泊松方程以及23种粒子间化学反应。分别在模型中对密度峰值和分布位置预设置3个不同数值,研究初始种子电子团密度峰值和分布位置对空气间隙流注放电行为的影响。结果表明:初始种子电子团密度峰值的增加只会加速流注的形成,不会影响流注的时空变化规律;而分布位置的改变会影响流注的时空发展特性,初始位置与棒电极的距离越远,形成的流注到达板电极的时间愈短。

The number and location of initial seed electron cluster during streamer discharge are random.In order to reveal the influence of initial seed electron cluster on the streamer discharge, a hydrodynamical-chemical reaction mixed model was established to simulate the streamer discharge in5 mm rod-plate gap at atmospheric pressure. The model includes electrons, positive and negative ion continuity equations, electron mean energy equations, Poisson equation of electric field, and 23 kinds of chemical reactions between particles. In the model, the peak density and distribution position are preset three numerical values, and their effect on the streamer discharge was studied. The results show that the increase of the density peak of initial seed electron cluster only accelerates the formation of streamer,and does not affect the space-time change law of streamer. The change of distribution position would affect the space-time development characteristics of streamer, and the farther the distance between initial position and rod electrode, the earlier the streamer gets to the plate electrode.