HL-2A装置上刮削层丝状结构时空特征的实验研究  

Experimental study of the SOL blob spatio-temporal characteristics in HL-2A tokamak

作　　者：朱有敬 程钧 严龙文[2] 王威策 黄治辉 吴娜 许宇鸿 石中兵[2] 季小全[2] 钟武律[2] 许敏[2] ZHU You-jing;CHENG Jun;YAN Long-wen;WANG Wei-ce;HUANG Zhi-hui;WU Na;XU Yu-hong;SHI Zhong-bing;JI Xiao-quan;ZHONG Wu-lü;XU Min(School of Physical Science and Technology,Southwest Jiaotong University,Chengdu 610031;Southwestern Institute of Physics,Chengdu 610041)

机构地区：[1]西南交通大学物理科学与技术学院,成都610031 [2]核工业西南物理研究院,成都610041

出　　处：《核聚变与等离子体物理》2024年第3期334-342,共9页Nuclear Fusion and Plasma Physics

基　　金：国家自然科学基金面上项目(12175186)。

摘　　要：在HL-2A装置上,采用环向相距2100mm的组合探针阵列研究了刮削层涨落谱特征和阵发性丝状结构(blob)动力学过程。实验结果表明,沿磁力线方向静电涨落具有强的环向长程相关性,平行波数接近0,符合交换模的特征。电子回旋共振加热(ECRH)期间,在最后闭合磁面外侧形成径向宽度约1.0cm的E×B剪切层,它对经过该区域的blob具有一定的拉伸作用。条件平均方法分析指出,ECRH期间相比于欧姆加热条件下blob极向尺寸仅增加了20%~30%,但blob内部电势差增大了约40%~60%,暗示了blob内部电势差增加是导致blob径向速度增加的主要原因。这些实验结果为ECRH期间观察到blob阵发性输运的增加提供了一种解释,对理解blob径向速度定标律以及控制blob对流输运具有重要的意义。The spectral characteristics of the scrape-off layer(SOL)electrostatic fluctuations and blob dynamics have been studied by using two Langmuir probe arrays toroidally separated by 2100mm in HL-2A tokamak.The experimental results demonstrated that the fluctuation along the magnetic field line has the significant toroidal long-range correlation and the estimated parallel wavenumber is almost zero.These characteristics are well consistent with the theoretically predicated interchange instability.An E×B shear layer close to 1.0cm width forms just outside the LCFS during the ECRH,which has the ability to stretch the passing blobs.Conditional average analysis shows the potential difference in one blob increases by up to 40%~60%in ECRH,compared to that in Ohmically-heated plasma,which is much larger than the variation of blob poloidal size(20%~30%).This experimental finding presented here reveals that the increased internal potential difference is the main cause for driving the blobs to move outward quickly.Therefore,this study provides an alternative interpretation for the additionally intermittent transport observed in ECRH and could help understand the behind physics on blob radial velocity scaling and find suitable control methods for suppression of the blob convective transport in future.

关 键 词：刮削层 丝状结构动力学 环向长程相关 E×B剪切流 朗缪尔探针 

分 类 号：TL656[核科学技术—核技术及应用]