HL-3装置欧姆等离子体中高频磁流体不稳定性的实验观测  

Observation of high-frequency magnetohydrodynamics instability in HL-3 Ohmic plasmas

作　　者：杨秋磊 陈伟 张洁 程时葵 梁绍勇 张轶泼 HL-3实验团队 YANG Qiu-lei;CHEN Wei;ZHANG Jie;CHENG Shi-kui;LIANG Shao-yong;ZHANG Yi-po;HL-3Experimental Team(Southwestern Institute of Physics,Chengdu 610041)

机构地区：[1]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328-333,共6页Nuclear Fusion and Plasma Physics

基　　金：国家自然科学基金杰出青年项目(12125502);国家重点研发专项(2019YFE03020000)。

摘　　要：在HL-3装置1MA电流等离子体欧姆放电实验期间,米尔诺夫(Mirnov)探针测量到两种高频磁流体(MHD)不稳定性。在等离子体启动阶段,电流爬升受到抑制,碘化钠探测器测量到逃逸电子增加。同时Mirnov探针测量到多分支频率f为20~400k Hz的高频MHD不稳定性。结果表明,这种不稳定性的出现与逃逸电子增加密切相关,并抑制了等离子体电流的爬升,损失了大约7%伏秒数。等离子体电流和密度爬升时,Mirnov探针测量到频率f为110~160k Hz的高频MHD不稳定性。这种不稳定性频率与芯部阿尔芬频率成正比,处于环向阿尔芬本征模频率范围。随着这种不稳定性的演化,等离子体发生了破裂。这些高频MHD不稳定性的研究对于HL-3后续放电及未来ITER的初始放电有重要的参考意义。This article describes the experimental observation obtained from HL-3 Ohmic plasma,using magnetic probe diagnostics.This measurement reveals the presence of two type high-frequency magnetohydrodynamics(MHD)instability in plasma.During the plasma start-up phase,the current rise is inhibited at t≈40ms and sodium iodide(NaI)detector measures enhancement of runaway electrons.At the same time magnetic probe diagnostics measure multi-branch upward-swept high-frequency MHD instability with a frequency range of f is 20~400kHz.The results indicate that the instability,which is related to enhancement of runaway electrons,inhibits the plasma current rise with a loss of about 7%volt-second.When the plasma current and density are in climbing stage,magnetic probe diagnostics detects a downward-swept high-frequency MHD instability with a frequency range of f is 110~160kHz.The frequency of instability is proportional to the core Alfvén frequency,which lies in the toroidal Alfvén eigenmode(TAE)frequency range.The plasma discharge is terminated as the instability evolves.The study of the high-frequency MHD instability has important reference for the subsequent discharge of HL-3 tokamak and the initial discharge of ITER in future.

关 键 词：等离子体 磁流体不稳定性 逃逸电子 破裂 

分 类 号：TL62*2[核科学技术—核技术及应用]