极坐标系下等离子体模拟的粒子推进算法

提出了一种在极坐标系下快速推进带电粒子的等离子体粒子模拟算法,该算法在每个时间步长内对带电粒子位置附近的区域采用局部直角坐标系近似,并通过坐标变换,得到粒子运动方程求解的显式格式,从而避免了极坐标系下隐式格式直接迭代求解所带来的容许误差,并提高了计算效率.数值实验表明:显式粒子推进算法的计算速度比容许误差取10-3时的隐式算法提高了约1倍.该算法可用于轴向均匀等离子体器件和高功率微波器件的2 5维粒子模拟.

Particle-Moving Algorithm for Particle-in-Cell Simulation of Plasmas in Polar Coordinates System

A fast particle-moving algorithm for particle-in-cell simulation of plasmas in polar coordinates system was proposed, in which the local rectangular coordinates approximation was used in the area near the position of the charged particle at every time step. By coordinate transformation, an explicit solution scheme of the particle motion equation was derived to avoid the error,which is always brought in the direct iteration process of the implicit algorithm under polar coordinates system, and enhances the computational efficiency. Numerical simulation results show that, compared with the implicit algorithm with 10~(-3) tolerance, the speed of the new explicit algorithm is increased to about 2 times for the whole particle-mover. The algorithm proposed can be used in 2.5-dimensional particle-in-cell simulation of longitudinal homogeneous plasmas and high-power microwave devices.