Time: Thursday, Nov. 4th, 4:00pm
Venue: Room 413, Buil. 11th, YuQuan Campus
Speaker: 陈文锦
Title: 动态磁岛中自举电流的动理学模拟
Abstract: 在托卡马克装置中,由于磁岛内平化压强分布导致自举电流份额降低,从而使得新经典撕裂模(NTM)爆发性增长。NTM发展会引起磁场拓扑结构的大幅度改变,这不仅限制了等离子体的比压极限,而且会引起放电的破裂。在NTM磁流体数值研究工作中,自举电流主要是采用磁流体磁面平均的表达式,忽略了极向分布的细节,而漂移动理学粒子模拟结果表明自举电流具有极向不对称性特征。另外,在之前动理学粒子模拟自举电流中,磁岛是静态,还未考虑到动态的磁岛。然而在NTM发展过程中,磁岛动态演化诱发的电场会加速粒子,影响了自举电流分布和份额。该报告主要介绍:采用动理学粒子模拟自举电流在平衡场,静态磁岛和动态磁岛中分布。
speaker:王亚辉
Title:Nonlinear excitation of geodesic acoustic mode by reversed shear Alfven eignemodes
Abstract: The parametric decay process of reversed shear Alfven eigenmeode (RSAE) into a geodesic acoustic mode (GAM) and kinetic reversed shear Alfven eigenmode (KRSAE) is investigated using nonlinear gyrokinetic theory. The excitation condition mainly requires the pump RSAE amplitude to exceed a certain threshold, which could be readily satisfied in burning plasmas operated at steady-state advanced scenario. This decay process can contribute to thermal plasma heating and confinement improvement.