Applications of Relativistic Structure-preserving Particle Algorithms in Multi-scale Plasma Processes
报告人:王雨雷博士,中国科技大学 时间:2019年12月18日14:00
报告地点:行健楼学术活动室526
邀请人:王雨顺教授
摘要:
As typical multi-body systems, plasmas contain massive charged particles which are coupled with inner and outer electromagnetic fields. It is difficult to describe such complex systems through pure theoretical methods, especially for nonlinear and multiscale plasma processes. Thus, the numerical simulation has become a widely-used tool for researchers especially after the rapid boost of computer technology in last decades. But, the simulations of multi-scale phenomena are still hampered by limited computation resources and accumulation of numerical errors. To achieve efficient and accurate usages of future massive computation resources, algorithms with long-term stability are also needed. The structure-preserving algorithms, through preserving geometric structures of physical systems, can effectively control the global errors during multi-scale simulations. 
In this report, the applications of structure-preserving particle algorithms for relativistic plasma systems are introduced. For simulating dynamics of energetic charged particles, the relativistic volume-preserving algorithm (VPA) and the new conception of Lorentz covariant canonical symplectic algorithm are represented. New multi-scale physical phenomenon, the collisionless pitch-angle scattering, is discussed, the discovery of which benefits by the secular stability of structure-preserving algorithms. To boost the usages of advanced algorithms, developments of HPC software are necessary. The idea of building extensible software platforms for structure-preserving particle algorithms will also be introduced.