Time: Wednesday, March 23, 4:00pm
Venue: Room 413, Buil. 11th, YuQuan Campus
报告1: 张敏20220323
题目:
偏滤器位形中边缘局域模不稳定性的线性模拟
摘要:
在托卡马克装置H模放电过程中,等离子体边界会出现周期性扰动的边缘局域模(ELM)。主流的MHD理论认为ELM不稳定性是由边界的压强梯度和局域电流共同驱动,并根据二者驱动的强弱划分为以压强梯度驱动为主导的气球模、电流驱动为主导的剥离模和二者共同驱动的剥离-气球模。我们利用平衡代码CLT-EQ构造了具有H模放电特性的平衡位形,对这三种不稳定模式转换对边界压强和电流的依赖关系进行了定量研究。初步模拟发现在具有外部台基特性的压强分布下,增加台基区的电流,会出现三种不同的不稳定性模式:气球模、剥离-气球模和剥离模。磁剪切对这些模式转换和同一模式下增长率的变化有着主导作用。
报告2 黄家兴 20220323
title:
Numerical study of excitation and saturation of NTM by CLT
Abstract:
Tearing modes often limit the performance of tokamak plasmas, or even lead to a disruption. For high beta plasmas, a particularly dangerous instability is the neoclassical tearing mode, which is driven by the perturbed bootstrap current. We have improved the numerical method for the calculation of the parallel heat transport in CLT, and then studied the excitation and saturation of NTM