Symplectic integrators with adaptive time step applied to runaway electron dynamics

被引:0
作者
Yanyan Shi
Yajuan Sun
Yang He
Hong Qin
Jian Liu
机构
[1] CAS,LSEC, ICMSEC, Academy of Mathematics and Systems Science
[2] University of Chinese Academy of Sciences,School of Mathematical Sciences
[3] University of Science and Technology,School of Mathematics and Physics
[4] Princeton University,Plasma Physics Laboratory
[5] USTC,Department of Engineering and Applied Physics
[6] CAS,Key Laboratory of Geospace Environment
来源
Numerical Algorithms | 2019年 / 81卷
关键词
Runaway electrons; Symplectic methods; Adaptive time step;
D O I
暂无
中图分类号
学科分类号
摘要
Studying the dynamics of runaway electrons has theoretical and practical significance. As the system is highly relativistic, multi-scale and nonlinear, accurate and efficient numerical methods with long-term stability are necessary. In this paper, we develop symplectic methods with adaptive time step and discuss the choice of step-size functions in accordance with the simulation problems for runaway electrons. In the implementation, in order to explore the practical impact of runaway electron dynamics, we use the electromagnetic field and some parameters often used in the study of plasma problems. Numerical results show that the new derived symplectic methods with adaptive time step exhibit good invariant-preserving property and superior stability over longtime integration. Moreover, with appropriate adaptive technique, the numerical efficiency in simulations is improved apparently. They are illustrated in the numerical experiments.
引用
收藏
页码:1295 / 1309
页数:14
相关论文
共 59 条
[1]  
Dreicer H(1959)Electron and ion runaway in a fully ionized gas Phys. Rev. 115 238-249
[2]  
Kulsrud RM(1973)Runaway electrons in a plasma Phys. Rev. Lett. 31 690-328
[3]  
Sun YC(1997)Theory for avalanche of runaway electrons in tokamaks Nucl. Fusion 37 1355-470
[4]  
Winsor NK(1994)Impact of runaway electrons Fusion Eng. Des. 23 323-295
[5]  
Fallon HA(2001)A synchrotron radiation diagnostic to observe relativistic runaway electrons in a tokamak plasma Rev. Sci. Instrum. 72 466-S202
[6]  
Rosenbluth M(2016)Collisionless pitch-angle scattering of runaway electrons Nucl. Fusion 56 064002-undefined
[7]  
Putvinski S(2010)Phase-space dynamics of runaway electrons in tokamaks Phys. Plasmas 17 092502-undefined
[8]  
Bartels HW(2017)Explicit symplectic methods for solving charged particle trajectories Phys. Plasmas 24 052507-undefined
[9]  
Jaspers R(2018)Explicit symplectic algorithms based on generating functions for relativistic charged particle dynamics in time-dependent electromagnetic field Phys. Plasmas 25 022117-undefined
[10]  
Cardozo NJL(2015)Volume-preserving algorithm for secular relativistic dynamics of charged particles Phys. Plasmas 22 044501-undefined