大量氘氩/氖混合气体注入对托卡马克逃逸电流抑制的数值研究  

Numerical investigation of Tokamak runaway current suppression by using massive deuterium-argon/neon gas mixture injection

作　　者：韩真哲 郑平卫 HAN Zhenzhe;ZHENG Pingwei(School of Resource Environment and Safety Engineering,University of South China,Hengyang 421001,China;Demonstration Base for International Science and Technology Cooperation on Nuclear Energy and Nuclear Safety,University of South China,Hengyang 421001,China)

机构地区：[1]南华大学资源环境与安全工程学院,衡阳421001 [2]南华大学核能与核安全国际科技合作示范基地,衡阳421001

出　　处：《核技术》2024年第8期98-106,共9页Nuclear Techniques

基　　金：国家重点研发计划(No.2022YFE03070000,No.2022YFE03070003);国家自然科学基金(No.12375220);湖南省自然科学基金(No.2021JJ30569);南华大学博士启动基金项目(No.190XQD114);湖南省核聚变国际科技创新合作基地(No.2018WK4009);衡阳市磁约束核聚变研究重点实验室(No.2018KJ108)资助。

摘　　要：托卡马克等离子体破裂会产生逃逸电流,如不进行抑制,其携带的巨大能量将对设备造成严重破坏。本文使用DREAM程序中的流体模型,基于中国环流器二号M(HL-2M)托卡马克装置大等离子体电流放电条件,研究注入氘氩/氖混合气体对破裂逃逸电流的影响。研究表明:注入氘氩/氖混合气体可以抑制最终形成的平台逃逸电流。在讨论的破裂前等离子体电流I_(p)范围内,最优条件下氩/氖在混合气体中的含量应在0.50%~0.70%,氘的注入量应在10^(20)~10^(21)m^(-3)。在这个范围外,氘氩/氖混合气体注入对逃逸电流的抑制效果都会减弱,甚至会增大逃逸电流。破裂前等离子体电流I_(p)是影响逃逸电流的关键因素。I_(p)越大,形成的逃逸电流越大,也需要注入更多的混合气体。在I_(p)高达10 MA的聚变堆级托卡马克装置上,注入混合气体的密度需要达到10^(22)m^(-3),这是目前大量气体注入(Massive Gas Injection,MGI)技术所不能达到的,通过散裂弹丸注入氘氩/氖混合物将是更加可行的方式。[Background]Tokamak plasma disruption generates a runaway current carrying enormous amounts of energy that,if not suppressed,can cause severe damage to equipment.[Purpose]This study aims to investigate the effects of injecting a deuterium-argon/neon gas mixture on a runaway current during plasma disruption.[Methods]Based on the high plasma current discharge conditions of the HL-2M tokamak device in China,numerical simulations were conducted using a fluid model in the DREAM code.Variations of plasma parameters,such as plasma current(I_(p)),ohmic current(Iohm),runaway current and the ohmic electric field,with the injected deuteriumargon content and ratio during the disruption process were consistently simulated.[Results]Results show that injecting a deuterium-argon/neon gas mixture suppresses the eventual formation of a platform runaway current,and an optimal content and ratio of the deuterium-argon/neon gas mixture are existed for effective runaway current suppression.Within the range of the pre-disruption plasma current(I_(p))discussed in this study,the amounts of neon/argon and deuterium in the gas mixture should be 0.50%~0.70%and 10^(20~10^(21)m^(−3),On fusion-reactor-scale tokamak devices with I_(p)as high as 10 MA,the amount of the injected gas mixture must reach 1022 m^(−3),which cannot be achieved under the current massive gas injection(MGI)technique.[Conclusions]The pre-disruption plasma current(I_(p))is the key factor that influences a runaway current.The larger I_(p)is,the larger is the runaway current that is formed and more amount of the gas mixture must be injected.On fusion-reactor-scale tokamak devices with I_(p)as high as 10 MA,the amount of the injected gas mixture must reach 1022 m^(−3),which cannot be achieved under the current massive gas injection technique.Injecting a deuterium-argon/neon gas mixture through a shattered pellet would be a more viable approach.

关 键 词：托卡马克 等离子体破裂 逃逸电流 大量混合气体注入 氘氩/氖混合气体 

分 类 号：TL631.2[核科学技术—核技术及应用]