Helium transport in the core and stochastic edge layer in LHD
Helium transport in the core and stochastic edge layer in LHD
复制标题
LHD 中的核心和随机边缘层中的氦传输
DOI：
10.1088/0741-3335/58/7/074010
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发表时间：
2016
影响因子：
2.2
通讯作者：
Y Nakamura1 and The LHD Experiment Group
中科院分区：
文献类型：
--
作者：
K Ida;M Yoshinuma;M Goto;O Schmitz;S Dai;A Bader;M Kobayashi;G Kawamura;C Moon;Y Nakamura1 and The LHD Experiment Group
在大螺旋装置中用双波长光谱仪测量了氦氢离子密度比的径向分布。氦输运在最后的封闭通量表面（LCFS）和随机磁场层外的LCFS以及在核心等离子体的氦馏分范围广泛，即从氢为主的等离子体氦为主的等离子体研究。在以氢为主的等离子体中，氦密度分布变得更加尖锐，向内对流速度增加，而在以氦为主的等离子体中，氦密度分布变得平坦或中空，对流速度是向外的。在LCFS处氦的密度梯度是氢的两倍，并且随着氢变得更占主导地位而变得更陡。
Radial profiles of the density ratio of helium to hydrogen ions are measured using charge exchange spectroscopy with a two-wavelength spectrometer in the large helical device. Helium transport at the last closed flux surface (LCFS) and stochastic magnetic field layer outside the LCFS as well as in the core plasma is studied for a wide range of helium fractions, ie from hydrogen-dominated plasmas up to helium-dominated plasmas. The helium density profile becomes more peaked and inward convection velocity increases in the hydrogen-dominant plasma, while it becomes flat or hollow and the convection velocity is in the outward direction in the helium-dominant plasmas. The density gradient of helium at the LCFS is twice that of hydrogen and becomes steeper as the hydrogen becomes more dominant.