EAST托卡马克上共振磁扰动对锯齿行为的影响  

Influence of resonant magnetic perturbation on sawtooth behavior in experimental advanced superconducting Tokamak

作　　者：潘姗姗 段艳敏 徐立清 晁燕 钟国强 孙有文 盛回 刘海庆 储宇奇 吕波 金仡飞 胡立群 Pan Shan-Shan;Duan Yan-Min;Xu Li-Qing;Chao Yan;Zhong Guo-Qiang;Sun You-Wen;Sheng Hui;Liu Hai-Qing;Chu Yu-Qi;Lü Bo;Jin Yi-Fei;Hu Li-Qun(Institute of Plasma Physics,Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院合肥物质科学研究院等离子体物理研究所,合肥230031 [2]中国科学技术大学,合肥230026

出　　处：《物理学报》2023年第13期134-141,共8页Acta Physica Sinica

基　　金：国家磁约束核聚变能发展研究专项(批准号:2022YFE03040003,2022YFE03010003);国家自然科学基金(批准号:11975273)资助的课题。

摘　　要：锯齿振荡是托卡马克装置上常见的磁流体不稳定性之一.先进实验超导托卡马克(experimental advanced superconducting Tokamak,EAST)装置放电中观察到外加共振磁扰动(resonant magnetic perturbation,RMP)会影响锯齿振荡行为.本文研究了环向模数n=2的RMP对锯齿周期的影响.通过RMP线圈相位差扫描实验发现,当RMP上下线圈(n=2)相位差ΔφUL发生变化时,扰动场的谱型发生变化,锯齿周期和崩塌幅度也随之发生明显的改变.单流体电阻磁流体力学(MARS-F)程序分析表明,在相同实验条件下,当RMP上下线圈(n=2)相位差为ΔφUL=270°时,等离子体芯部区域的响应最强,此时锯齿周期和幅度最小.锯齿行为的改变可能与RMP引起的快离子损失相关.该研究利用RMP上下线圈(n=2)实现对锯齿行为的有效调控,有利于未来EAST发展高比压放电条件下的大锯齿自动控制技术.Sawtooth oscillation is one of the most important magneto-hydrodynamic(MHD)instabilities in Tokamak plasma,which can result in the periodic relaxation of the temperature and density of the core plasma when the safety factor on the magnetic axis(q0)is lower than unity.Owing to the periodic relaxation of the plasma core parameters,sawtooth oscillations are beneficial to avoiding impurity accumulation in plasma core.However,the large sawtooth crash may trigger off other MHD instabilities,like tearing modes(TMs)or neoclassical tearing modes(NTMs),which is a matter of concern for the plasma stability.Therefore,it is essential to control sawtooth oscillations for ensuring safe operation in the future Tokamaks such as ITER.The resonant magnetic perturbation(RMP)is widely used to control edge-localized modes(ELMs)and divertor heat flux in Tokamak.The application of RMP has also been found to affect the sawtooth behaviors.This paper studies the influence of RMP coils at n=2 on sawtooth behaviors in experimental advanced superconducting Tokamak(EAST),where n is the toroidal mode number of the applied RMP.It is found that the phase difference between upper∆ϕUL(◦)=ϕU(◦)-ϕL(◦)RMP coil and lower RMP coil()is a notable parameter of affecting sawtooth behavior.∆ϕUL∆ϕULThe experiments for scanning the phase difference are carried out.When the phase difference of RMP at n=2 is changed,the sawtooth period and amplitude become subsequently different.The minimum∆ϕUL=270◦sawtooth period and amplitude appear at.At the same time,neutron yields measured by neutron diagnostic system have the same trend as sawtooth behavior during RMP phase difference scanning.The plasma response to RMP at n=2 is analyzed by using the MARS-F code.The results show that the plasma∆ϕUL=270◦responses much strongly at the.The loss of fast ion,caused by RMP coils,is possibly stronger at∆ϕUL=270◦∆ϕUL.the than that at other phase difference The loss of fast ion can reduces its stabilization effect on sawtooth behavior,which resul

关 键 词：先进实验超导托卡马克 共振磁扰动 锯齿振荡 

分 类 号：TL631.24[核科学技术—核技术及应用]