论文标题
ASDEX升级中的I型边缘局部模式周期的非线性扩展MHD模拟及其基础触发机制
Non-linear extended MHD simulations of type-I edge localised mode cycles in ASDEX Upgrade and their underlying triggering mechanism
论文作者
论文摘要
通过首次执行重复的I型E ELM的非线性磁性水力动力学模拟，可以鉴定出负责融合等离子体中边缘局部模式（ELM）爆炸性爆炸性局部模式（ELM）的触发机制。短暂地，在榆树崩溃之前，在不同的时间尺度上，不稳定和稳定项会受到越来越多的偏执磁场的影响，这是由于轴心对称背景等离子体和不断增长的非轴对称扰动之间的非线性相互作用引起的。时间尺度的分离促使爆炸物，即比指数快，榆树崩溃的增长持续$ {\ sim} $ 500 $μ$ s。模拟ELM的持续时间和大小崩溃与ASDEX升级中的I型ELMS的定性比较。正如I型ELMS所预期的那样，获得了模拟中的加热能力与ELM重复频率之间的直接比例。此处提供的模拟是迈向榆树的预测建模以及对ITER和其他未来Tokamaks中缓解技术的评估的重要一步。
A triggering mechanism responsible for the explosive onset of edge localised modes (ELMs) in fusion plasmas is identified by performing, for the first time, non-linear magnetohydrodynamic simulations of repetitive type-I ELMs. Briefly prior to the ELM crash, destabilising and stabilising terms are affected at different timescales by an increasingly ergodic magnetic field caused by non-linear interactions between the axisymmetric background plasma and growing non-axisymmetric perturbations. The separation of timescales prompts the explosive, i.e. faster than exponential, growth of an ELM crash which lasts ${\sim}$ 500 $μ$s. The duration and size of the simulated ELM crashes compare qualitatively well with type-I ELMs in ASDEX Upgrade. As expected for type-I ELMs, a direct proportionality between the heating power in the simulations and the ELM repetition frequency is obtained. The simulations presented here are a major step forward towards predictive modelling of ELMs and of the assessment of mitigation techniques in ITER and other future tokamaks.
