时间：2025年12月8日（周一）14:00
地点：紫金港校区海纳苑8幢324教室
报告题目：Plasma parallel transport physics in a tokamak thermal quench and its mitigations
报告人：张彦增
摘要：
A nearly collisionless fusion-grade plasma can undergo a swift thermal collapse triggered by impurity radiation or the loss of magnetic confinement. Such plasma thermal quench (TQ) can occur in all magnetically confined plasmas, but is particularly important in current-carrying tokamaks. In tokamak disruptions, the TQ not only imposes severe thermal loads on divertor plates and first wall, but also determines the runaway seeding for the subsequent current quench. The 3-4 orders of magnitude faster plasma energy loss rate during TQ than in steady-state operation is intuitively understood as the result of parallel transport along open magnetic field lines dominating over perpendicular transport. The normal expectation is that such parallel transport of plasma thermal energy in the short magnetic connection length regime represents a worst-case scenario of a TQ in tokamaks, where the plasma thermal energy is released in the shortest possible time. Therefore, understanding the plasma TQ in such an exotic regime with extreme plasma kinetics, which have been largely missed in previous studies with MHD simulations, is critical for disruption mitigation. By employing fully kinetic VPIC simulations and analytical theory, we have demonstrated a fundamentally different physical picture of how rapid plasma cooling occurs, with significant implications for designing disruption mitigation strategies in next-generation fusion reactors.
个人简介：
张彦增博士本科毕业于中国科大，于2020年获加利福尼亚大学圣地亚哥分校博士学位，先后在美国洛斯阿拉莫斯国家实验室任主任博士后及二级科学家，并于 2025 年 7 月加入中国科大，任特任研究员。长期致力于磁约束聚变等离子体的理论与数值模拟研究，在托卡马克破裂、边界等离子体输运等方向取得了一些创新性成果，在 Physical Review Letters、Nuclear Fusion、Physics of Plasmas 等等离子体领域权威期刊发表论文 30 余篇，其中第一作者论文 20 余篇，担任 Nature Communications、Scientific Reports、Physics of Plasmas 等多个期刊审稿人。
欢迎各位老师和同学参加！
