摘要
特定脉冲放电参数条件下,原来沿直线传播的低温等离子体射流放电通道会在脉冲电磁驱动下发生放电模式转换,形成螺旋形态的流注通道.与传统的螺旋波放电不同,实验中并没有外加恒定磁场等破坏介质管极向对称性的因素,而且螺旋的手性方向会随放电参数变化.为深入了解等离子体射流中螺旋结构的电磁作用机理,探索其导致螺旋形态和决定手征性的极向电场来源及影响因素,本文通过建立完备自洽的等离子体理论模型,对螺旋流注的手性方向、螺距变化、分叉等复杂放电特性和电磁机理进行分析.研究发现击穿时极向电场波模的初始相位对螺旋流注的手性选择存在影响,电子密度对螺旋流注的螺距参数存在影响,放电的脉冲重复频率对螺旋流注分叉的分叉点位置存在影响.以上放电特性及其影响因素对探明电磁波与等离子体的相互作用机制具有重要科学意义,同时也为低温等离子体的手性应用提供实验和理论支撑.
Under the condition of specific pulsed discharge parameters,the discharge mode conversion of the lowtemperature plasma jet discharge channel that originally propagates along a straight line will occur,forming a three-dimensional helical plasma channel.Unlike the traditional helical wave discharge,there are no factors such as an external constant magnetic field that destroys the poloidal symmetry of the dielectric tube,and the chiral direction of the helical streamer will change with the discharge parameters.In order to understand in depth the electromagnetic mechanism of the helical structure in the plasma jet,and the source and influencing factors of the poloidal electric field that leads to the helical shape and determines the chirality in this new type of discharge,we analyze the complex characteristics and electromagnetic mechanism of the helical streamer,such as the chiral direction,pitch,branching,by establishing a self-consistent plasma theoretical model.It is found that the phase of the poloidal wave mode has an effect on the chiral selection of the helical streamer,that the electron density has an influence on the pitch of the streamer,and that the repetition frequency has an effect on the bifurcation point.The above discharge characteristics and their influencing factors are of scientific significance in exploring the interaction mechanism of electromagnetic wave and plasma,and also in providing experimental and theoretical support for the chiral application of low-temperature plasma.
作者
邹丹旦
涂忱胜
胡平子
李春华
钱沐杨
Zou Dan-Dan;Tu Chen-Sheng;Hu Ping-Zi;Li Chun-Hua;Qian Mu-Yang(East China Jiaotong University,Nanchang 330013,China;Hefei University of Technology,Hefei 230009,China;Nanchang University,Nanchang 330031,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2023年第11期267-274,共8页
Acta Physica Sinica
基金
国家自然科学基金(批准号:12005061,12065019)
中国博士后科学基金(批准号:2019M662271)资助的课题.
关键词
等离子体
螺旋流注
手性
脉冲放电
plasma
helical streamer
chirality
pulsed discharge
