J-TEXT 学术报告第36期
报告人1： 张正卿（HUST）
题 目1： TBM测试电磁模块在等离子体破裂时的载荷研究进展与计划
摘要：
在聚变反应堆中，包层担负着氚的供给，核素转换，高级能量转换及提取作用。实验包层模块（Test Blanket Module，TBM），将要在ITER上进行上述功能及安全评估实验验证。聚变堆等离子体破裂时所产生的瞬态电磁和热载荷对堆内部件(包层、偏滤器等)冲击破坏机理及其预防减缓技术研究，是磁约束聚变堆设计运行的关键科学技术问题之一。为解决这一科学技术问题，需要研究破裂时等离子体与TBM模块等堆内部件结构的相互作用机制；研究破裂时瞬态电磁和热载荷的诊断测量方式；利用数值模拟与实验验证相结合的方法，掌握相关载荷的时空分布规律。
J-TEXT
TBM测试电磁模块是依据中国HCCB-TBM结构,以RAFM钢(Reduced activation ferritic/martensitic
steel)为结构材料，省略了TBM内部的功能子模块，按照三分之一的比例设计的TBM 结构框架。本课题通过将TBM测试电磁模块与J-TEXT装置安装集成，并开展主动等离子体破裂实验，获取破裂条件下模块电磁载荷时空分布数据。在此基础上研究模块与等离子体作用方式，归纳电磁载荷产生机理，为TBM结构的优化设计、安全性分析提供实验数据和依据，进而研究堆内部件受强瞬态电磁载荷与高热流冲击破坏时的减缓方法与措施,同时演示和验证中国HCCB-TBM的结构电磁相关技术。
目前， J-TEXT TBM测试电磁模块已完成了接口组件的设计与安装调试，利用仿真模拟分析了模块对平衡场位型的改变，并开展了模块对纵场纹波度影响的实验测量。完成了电磁及热载荷测量系统的设计搭建与标定，现阶段正进行接口组件的总装配。鉴于模块铁磁结构材料对磁场的影响，相关实验计划仍需进行评估与合理安排，以确保载荷测量系统的准确性与完整性，同时保证装置正常放电与安全运行。
报告人2： 魏禹农（HUST）
题 目2： Dissipation of
runaway current by MGI on J-TEXT
摘要：
Plasma disruption is one of
the major challenges for ITER. Severe energy releases in several milliseconds
during disruption phase can destroy the first wall. Transforming the
pre-disruption plasma current into runaway current and dissipating it maybe one
of the way to mitigate the energy release. Argon impurities injected into
runaway current plateau by Massive gas injection (MGI) valve have been tested
in several experimental condition on J-TEXT. Runaway currents are formed by
1019 argon atoms
injection, and then a large quantities of argon impurities are injected for
runaway electron (RE) current dissipation. For 100kA runaway current, we find
that the decay rate increases almost linearly with the gas injected rising, and
then reaches to a peak value
vmax=27MA/s which is
decided by the runaway electron energy and average decay time. The tendency of
decay rate changing with gas injection can be described as an experiential
exponential curve. Experiments with same impurities injected in different time
after disruption lead to a conclusion that impurities injected in CQ phase can
get better effect on RE current decay rate than in plateau phase. At last, a
few discharges with different RE currents indicate that runaway current with higher
energy will be dissipated more difficultly.
