在HT-7托卡马克上密度扫描实验中的边界湍流和输运

在HT-7托卡马克上密度扫描实验中使用一个快速扫描气动朗缪尔探针来研究边界湍流和输运。随着中心弦平均等离子体密度的增加，在等离子体边界观察到径向电场剪切增强，径向电场的增强能够解释边界输运的减小和全局粒子约束的改善。粒子约束时间的增加和垂直扩散系数的减小证明粒子输运降低了。在等离子体边界区域发现电离和辐射驱动湍流的特征，表明电离和辐射在湍流驱动过程中具有重要性。

Boundary turbulence and transport in density scanning experiment on TH-7 tokamak

The boundary turbulence and transport in density scanning experiment were investigated using a fast reciprocating Langmuir probe in the HT-7 tokamak.With the increase of the central line averaged plasma density, an enhanced shear of the radial electric field was observed at plasma edge, which could account for the reduction of edge transport and the improvement of global particle confinement. The reduced particle transport was demonstrated by the increase of the particle confinement time and the decrease of the perpendicular diffusion coefficient. The features of the ionization-and-radiation-driven turbulence, ${\tilde {T}_\e } \mathord{\left/{\vphantom {{\tilde {T}_\e } {T_\e }}} \right. \kern-\nulldelimiterspace} {T_\e}\sim {\tilde {n}_\e } \mathord{\left/ {\vphantom {{\tilde {n}_\e } {n_\e }}}\right. \kern-\nulldelimiterspace} {n_\e }$ and $\theta \_\tilde {T}_\e \tilde {n}_\e \sim \pi $, were found in the plasma edge region, which suggests the importance of the ionization and radiation in the turbulence driving.