粒子模拟中库仑碰撞算法的实现  

Coulomb Collision Algorithms in Particle in Cell Method

作　　者：任泽平 王玥[1] 陈再高[1] REN Ze-ping;WANG Yue;CHEN Zai-gao(Northwest Institute of Nuclear Technology,Xi’an 710024,China)

机构地区：[1]西北核技术研究所,西安710024

出　　处：《现代应用物理》2018年第1期54-59,共6页Modern Applied Physics

摘　　要：为了将PIC方法应用于高密度带电粒子系统的模拟,分析研究了TA碰撞算法和Nanbu碰撞算法,详细介绍了这两种碰撞算法的实现过程。给出了计算碰撞散射角的拟合公式,可提高Nanbu碰撞算法的效率。采用这两种碰撞算法分别模拟了等离子体中电子温度的平衡过程,通过与理论解进行比较,发现Nanbu碰撞算法在时间步长较大时,仍然可以得到与理论解吻合较好的模拟结果。最后,采用粒子模拟程序和库仑碰撞算法验证了等离子体双流体方程中动摩擦因数计算公式的正确性。To extend particle in cell method to simulate charged particle of high density,this paper investigates the principle of Coulomb collision.Two widely used Monte Carlo models for Coulomb collision due to Takizuka and Nanbu are explained in detail.A fitted formula to calculate scattering parameter in Nanbu’s method is introduced to accelerate this mehod.By using these two collision methods to simulate the temperature relaxation of plasma electron,we found Nanbu’s method is more efficient.Finally,the collision algorithm is applied to validate the dynamic friction factor in plasma fluid.

关 键 词：粒子模拟 库仑碰撞 等离子体 动摩擦因数 

分 类 号：O441[理学—电磁学]