三维非均匀磁场分布下低场峰产生时的波传播和能量沉积特性分析  

Analysis of Wave Propagation and Energy Deposition in Low-field Peaks under Three-dimensional Non-uniform Magnetic Field

作　　者：杜丹[1] 胡少雄 尹陈艳[3] 黄子文 喻翠 杨文军 周华 龚学余[3] DU Dan;HU Shaoxiong;YIN Chenyan;HUANG Ziwen;YU Cui;YANG Wenjun;ZHOU Hua;GONG Xueyu(School of Mathematics and Physics,University of South China,Hengyang 421001,China;School of Electrical Engineering,University of South China,Hengyang 421001,China;School of Nuclear Science and Technology,University of South China,Hengyang 421001,China;Institute of Plasma Physics,Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[1]南华大学数理学院,湖南衡阳421001 [2]南华大学电气工程学院,湖南衡阳421001 [3]南华大学核科学技术学院,湖南衡阳421001 [4]中国科学院合肥物质科学研究院等离子体物理研究所,安徽合肥230031

出　　处：《原子能科学技术》2024年第12期2462-2477,共16页Atomic Energy Science and Technology

基　　金：国家重点基础研究发展计划(2022YFE03070000,2022YFE03070001,2022YFE03070003);湖南省教育厅重点项目(20A432);湖南省自然科学基金(2020JJ4515)。

摘　　要：考虑粒子碰撞、化学反应和热效应,本文建立了右旋螺旋天线与柱状等离子体相互作用的三维模型,采用有限元法研究了3种三维非均匀磁场分布下右旋螺旋天线放电时的低场峰现象,并分析了密度峰产生时的波传播和功率沉积特性。主要模拟结果表明:在一定磁场大小范围内,随着最大磁场强度增加均存在密度峰现象,低于某阈值(B_(max)<120 G),低场峰产生时多普勒回旋阻尼和异常多普勒回旋阻尼致使的功率沉积占主导地位,且功率沉积峰值分布在螺旋波驻波附近;高于阈值时(B_(max)≥120 G),低场峰产生时碰撞阻尼致使的功率沉积占主导地位。螺旋波左、右旋极化电场同时在等离子体中传播,控制磁场分布,可控制低场峰产生时螺旋波极化电场的幅值、传播性质(行波、驻波、半驻波半行波)、功率沉积、密度和电子温度分布,螺旋波产生的驻波和功率沉积主要分布在磁场强度大的区域。相关研究结果对揭示螺旋波等离子体低场峰机制有一定指导意义。The helicon plasma exhibits the advantages of a high rate of ionization,high density and low confinement magnetic field.It has been widely used in plasma thruster,semiconductor etching,etc.The density of helicon plasmas would be monotonically dependent on the external magnetic field when the magnetic field intensity is sufficiently strong.However,it does not hold at low magnetic fields,which are characterized by a density peak(or low-field peaks).In this paper,a three-dimensional numerical model of argon helicon plasma discharge was established based on the detailed consideration of particle collision and chemical reaction.The characteristics of low-field peaks under different three-dimensional non-uniform magnetic field distributions were simulated and analyzed.The main simulation results show that there are density peaks with the increase of the maximum magnetic field intensity within a certain magnetic field range.Below a threshold(B_(max)<120 G),the power deposition caused by Dopplershifted cyclotron damping and anomalous Doppler damping is dominant when the low field peak occurs,and the power deposition peak is distributed near the standing helicon wave.Above the threshold(B_(max)≥120 G),the power deposition caused by collision damping is dominant.The distribution of power deposition caused by Landau damping and collision damping is close,mainly at the plasma edge and end plate.The left-hand polarization electric field component and right-hand polarization electric field component of the helicon wave propagate in the plasma simultaneously.By changing the magnetic field distribution,the amplitude of the polarization electric field component of helicon wave,propagation properties(traveling wave,standing wave,and partially travelling-partially standing wave),power deposition,density and temperature distribution can be controlled when the low field peak is generated.The standing wave and power deposition generated by helicon wave are mainly distributed in the region with high magnetic field.The relevant resear

关 键 词：螺旋波等离子体 低场峰 驻波 功率沉积 

分 类 号：TL61[核科学技术—核技术及应用] O53[理学—等离子体物理]