中国物理B ›› 2021, Vol. 30 ›› Issue (9): 95201-095201.doi: 10.1088/1674-1056/abefc7
Yifeng Zheng(郑艺峰), Jianyuan Xiao(肖建元)†, Yanpeng Wang(王彦鹏), Jiangshan Zheng(郑江山), and Ge Zhuang(庄革)
Yifeng Zheng(郑艺峰), Jianyuan Xiao(肖建元)†, Yanpeng Wang(王彦鹏), Jiangshan Zheng(郑江山), and Ge Zhuang(庄革)
摘要: A Monte Carlo implicit simulation program, Implicit Stratonovich Stochastic Differential Equations (ISSDE), is developed for solving stochastic differential equations (SDEs) that describe plasmas with Coulomb collision. The basic idea of the program is the stochastic equivalence between the Fokker-Planck equation and the Stratonovich SDEs. The splitting method is used to increase the numerical stability of the algorithm for dynamics of charged particles with Coulomb collision. The cases of Lorentzian plasma, Maxwellian plasma and arbitrary distribution function of background plasma have been considered. The adoption of the implicit midpoint method guarantees exactly the energy conservation for the diffusion term and thus improves the numerical stability compared with conventional Runge-Kutta methods. ISSDE is built with C++ and has standard interfaces and extensible modules. The slowing down processes of electron beams in unmagnetized plasma and relaxation process in magnetized plasma are studied using the ISSDE, which shows its correctness and reliability.
中图分类号: (Electron collisions)