按照章等[Zhang Y Z, Liu Z Y, Mahajan S M, Xie T, Liu J 2017 Phys. Plasmas 24 122304]发展的漂移波-带状流理论,将多重尺度导数展开法应用到电子漂移动理学方程,零级为描述微观尺度捕获电子模的线性本征模方程,一级为介观尺度受带...按照章等[Zhang Y Z, Liu Z Y, Mahajan S M, Xie T, Liu J 2017 Phys. Plasmas 24 122304]发展的漂移波-带状流理论,将多重尺度导数展开法应用到电子漂移动理学方程,零级为描述微观尺度捕获电子模的线性本征模方程,一级为介观尺度受带状流调制的捕获电子模的包络方程.其中线性本征模方程已经在谢等[Xie T, Zhang Y Z, Mahajan S M, Wu F, He Hongda, Liu Z Y 2019 Phys. Plasmas 26 022503]的研究中被求解,利用该文得到的捕获电子模的本征值和二维模式结构计算包络方程中的群速度.径向群速度由托卡马克磁场的测地曲率贡献,极向群速度来自逆磁漂移速度和法向曲率,它们仅是极向角的函数,后者给出极向角到时间的映射.径向群速度作为时间的函数,其周期在毫秒量级,具有快速过零的特征.这为研究捕获电子模驱动带状流提供了充实的理论基础.展开更多
We investigate the possibility of the usage of displaced current in Langmuir probe measurement theoretically and experimentally.The displaced current flows through the self-generated or artificial capacitance of the r...We investigate the possibility of the usage of displaced current in Langmuir probe measurement theoretically and experimentally.The displaced current flows through the self-generated or artificial capacitance of the reference electrode under an alternative sweep voltage.It can increase the total current afforded by the reference electrode,and eliminate the interference deriving from the finite plasma sheath resistance of the reference electrode.The results in both theory and experiment lead to the conclusion that the usage of displaced current is valid and more efficient with a floating probe method.This method is applied in some harsh plasma environments when the grounded chamber wall can easily be contaminated by the dielectric.展开更多
A low-frequency(f<2 kHz)potential structure(LFPS)is observed in a linear magnetic plasma device using Langmuir probe arrays.The center frequency of this structure is near zero.This structure has azimuthal and axial...A low-frequency(f<2 kHz)potential structure(LFPS)is observed in a linear magnetic plasma device using Langmuir probe arrays.The center frequency of this structure is near zero.This structure has azimuthal and axial symmetries while with a finite radial wavenumber.The complete 3D spectra features of this structure have been identified to have the characteristics expected for zonal flows.展开更多
文摘按照章等[Zhang Y Z, Liu Z Y, Mahajan S M, Xie T, Liu J 2017 Phys. Plasmas 24 122304]发展的漂移波-带状流理论,将多重尺度导数展开法应用到电子漂移动理学方程,零级为描述微观尺度捕获电子模的线性本征模方程,一级为介观尺度受带状流调制的捕获电子模的包络方程.其中线性本征模方程已经在谢等[Xie T, Zhang Y Z, Mahajan S M, Wu F, He Hongda, Liu Z Y 2019 Phys. Plasmas 26 022503]的研究中被求解,利用该文得到的捕获电子模的本征值和二维模式结构计算包络方程中的群速度.径向群速度由托卡马克磁场的测地曲率贡献,极向群速度来自逆磁漂移速度和法向曲率,它们仅是极向角的函数,后者给出极向角到时间的映射.径向群速度作为时间的函数,其周期在毫秒量级,具有快速过零的特征.这为研究捕获电子模驱动带状流提供了充实的理论基础.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10675121,10705028 and 10835009the ITER Domestic Program of China under Grant Nos 2009GB107000 and 2010GB107000.
文摘We investigate the possibility of the usage of displaced current in Langmuir probe measurement theoretically and experimentally.The displaced current flows through the self-generated or artificial capacitance of the reference electrode under an alternative sweep voltage.It can increase the total current afforded by the reference electrode,and eliminate the interference deriving from the finite plasma sheath resistance of the reference electrode.The results in both theory and experiment lead to the conclusion that the usage of displaced current is valid and more efficient with a floating probe method.This method is applied in some harsh plasma environments when the grounded chamber wall can easily be contaminated by the dielectric.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10875124 and 10605025the National Basic Research Program of China under Grant No 2008CB717800+2 种基金Research Fund for the Doctoral Program of Higher Education of China under Grant No 20060358059the ITER domestic program of China under Grant No 2010GB107000the Knowledge Innovation Program of Chinese Academy of Sciences under Grant No kjcx-yw-n28.
文摘A low-frequency(f<2 kHz)potential structure(LFPS)is observed in a linear magnetic plasma device using Langmuir probe arrays.The center frequency of this structure is near zero.This structure has azimuthal and axial symmetries while with a finite radial wavenumber.The complete 3D spectra features of this structure have been identified to have the characteristics expected for zonal flows.