HL-2A托卡马克等离子体的扭曲不稳定性研究  

Influence of Safety Factor and Poloidal Beta on Kink Instabilities of HL-2A Tokamak Plasma

作　　者：沈勇[1] 董家齐[2,1] 何宏达[1] 

机构地区：[1]核工业西南物理研究院,成都610041 [2]浙江大学聚变理论与模拟中心,杭州310027

出　　处：《真空科学与技术学报》2016年第4期447-453,共7页Chinese Journal of Vacuum Science and Technology

基　　金：国家磁约束核聚变能研究专项资助(2013GB111000,2015GB110002);国家自然科学基金资助项目(11175057,11475057)

摘　　要：扭曲模是托卡马克等离子体中一种常见的磁流体力学不稳定性。而安全因子(q)和比压(β)对扭曲模的产生、发展以及稳定化有着重要的、甚至是决定性的影响。本文从实验与模拟相结合的角度,基于HL-2A装置实验的一炮典型的偏滤器放电位形,研究了安全因子q和极向比压卢。对内扭曲模和外扭曲模的影响,分析了不同参数条件下的扭曲不稳定性。结果表明,当磁轴上的安全因子q_0<1时,内扭曲模有可能不稳定。当q_0>1时,内扭曲模是稳定的。而极向比压卢。对内、外扭曲模都有去稳作用,峰化的等离子体电流剖面(或安全因子剖面)对扭曲模有稳定作用。有关扭曲模稳定化措施中,必须综合考虑安全因子剖面和等离子体比压值,以利于实现托卡马克高性能放电。The kink mode,a common magnetohydrodynamic（MHD） instability of tokamak plasma,was mathemati cally modeled,theoretically analyzed,numerically simulated and experimentally evaluated.The influence of the safety factor（q） and poloidal beta（β_p）,in a typical divertor discharge configuration in a HL-2A experiment,on the internal and external kink modes was investigated.The results show that the safety factor and the poloidal beta significantly affect the kink instability.To be specific,when the safety factor on axis q_0 1,the internal kink mode may be unstable;but when q_0 1,it is stable.The poloidal betaβ_p de-stabilizes both the internal and external kink modes.Moreover,the shaped current and/or safety factor profiles stabilize the external kink modes.We suggest that the tokamak high-performanced discharges may be realized by stabilizing the kink modes with the optimized safety factor and poloidal beta in all possible stabilization measures.

关 键 词：磁流体力学不稳定性 扭曲模 安全因子 等离子体比压 HL-2A托卡马克 

分 类 号：TL631.24[核科学技术—核技术及应用]