均匀场中负流注放电形成过程粒子模拟

发布时间：2019-02-15 17:32

【摘要】：为研究均匀场中负流注放电的形成过程,采用粒子模拟方法对平行平板间隙中均匀场作用下高电压流注放电通道的形成和发展进行模拟,获取流注形成发展过程的瞬态物理图像和流注通道中心场强的变化图像。模拟结果表明:电子崩向阳极发展过程中,头部呈辐射状发展,尾部细长,电子集中在电子崩头部,当电子崩转变为流注后,流注通道中形成非平衡等离子体,通道头部和尾部局部场强增大,流注头部存在高能电子;在流注通道内的电子数密度分布图中观察到流注通道存在明显的分叉现象,不同气压和场强下通道分叉现象存在差异;场强一定时,流注发展速度受气压影响较小;气压一定时,随着场强增大,高能电子出现时间缩短,流注发展速度明显提高,通道中电子数密度显著增大,电离程度加深。
[Abstract]:In order to study the formation process of negative streamer discharge in uniform field, particle simulation method was used to simulate the formation and development of high voltage streamer discharge channel under the action of uniform field in parallel plate gap. The transient physical images of the formation and development of the streamer and the changing images of the central field intensity of the streamer channel are obtained. The simulation results show that during the development of electron avalanche to anode, the head develops radially, the tail is thin and the electron is concentrated on the electron avalanche head. When the electron avalanche is converted to a streamer, a non-equilibrium plasma is formed in the flow channel. The local field intensity increases at the head and tail of the channel and there are high energy electrons in the stream head. In the electron number density distribution map of the flow channel, obvious bifurcation phenomenon is observed in the flow channel, and the channel bifurcation phenomenon is different under different pressure and field intensity, and the velocity of the flow beam development is less affected by the pressure when the field intensity is constant. When the pressure is constant, with the increase of the field strength, the emergence time of high-energy electrons is shortened, the developing speed of streamer is obviously increased, the number density of electrons in the channel increases significantly, and the degree of ionization is deepened.
【作者单位】：西安交通大学电子物理与器件教育部重点实验室;西北核技术研究所;
【基金】：国家自然科学基金(51277147)~~
【分类号】：TM723

【参考文献】