水中正极性丝状流注放电发展特性  

Propagation characteristics of positive filamentary streamer discharges in water

作　　者：温嘉烨 王亚桢 肖正光 王骏东 李元 张冠军[2] Wen Jiaye;Wang Yazhen;Xiao Zhengguang;Wang Jundong;Li Yuan;Zhang Guanjun(State Grid Suzhou Power Supply Company,Suzhou 215000,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]国网江苏省电力有限公司苏州供电分公司,江苏苏州215000 [2]西安交通大学电气工程学院,西安710049

出　　处：《强激光与粒子束》2024年第10期91-100,共10页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(52242706)。

摘　　要：水中流注放电为击穿前放电通道起始与发展的关键过程,但由于涉及物理机制较为复杂且尚不明确,制约了水中放电应用效率的提升。探究了水中正极性丝状流注放电的模式转化特性、重燃特性与分叉特性,明确了通道界面沉积电荷与空间电荷分布对流注发展过程的影响。研究结果表明,水中正极性放电可分为第一类与第二类丝状流注,流注模式转化特性受气液界面电荷弛豫过程影响较大。当外施电压达到加速电压时,第一类流注迅速转化为第二类流注。第一类丝状流注通道内电离形成、熄灭及重燃过程与通道内部电场及气/液界面电荷密度关系密切。第二类丝状流注通道空间电荷分布受电压上升沿与电极表面结构影响较大。电压上升沿时间越长,主通道头部电荷密度与电场强度越低,通道发展速度随之降低。随电极表面微凸结构半径增大,流注分叉点位置将电极表面过渡为主通道根部。受主通道空间电荷分布影响,分支通道发展速度在微凸结构半径为5 μm时呈现先降后升趋势。Positive underwater discharge can produce abundant physical and chemical effects and is widely used in the fields of energy source exploration and sterilization.However,the physical mechanisms involved in initiation and propagation of streamer are complex and have not been fully revealed,which limit the efficiency of underwater discharge applications.In this paper,we explore the mode-transition,reillumination and branching characteristics of positive filamentary streamer.The influence of deposited charge and space charge distribution on the propagation of streamer channel is clarified.Our research shows that the positive polarity filamentary streamers can be divided into primary streamer and secondary streamer,and the mode transition of discharges is greatly affected by the gas/liquid interface charge relaxation process.When the applied voltage reaches the accelerating voltage,the primary streamer rapidly transits into secondary streamer.The gas/liquid interface charge density and electric field in primary streamer channel are closely related with initiation,termination and reignition of discharge.The space charge distribution of secondary streamer is greatly affected by the voltage rising edge and the electrode surface structure.Longer voltage rise time leads to lower density of space charge and electric field at the head of streamer channel,which causes the decrease of streamer velocity.With larger radius of the micro-convex structure on the electrode surface,the branching of streamer will take place at the root of the main channel instead of electrode surface.Due to the variation of the spatial charge distribution,the velocity of the branching channel shows a trend of first declining and then increasing when the radius of the micro-convex structure is 5μm.

关 键 词：液体放电 流注放电 放电模式 界面电荷 流注分叉 

分 类 号：TM85[电气工程—高电压与绝缘技术]