模擬電漿系統時，使用粒子網格模擬法(PIC)會造成離散粒子效應，它會縮短 數值熱化的時間也可能會影響到一些電漿的動力學行為。我們發現可以用取很多 組數據平均的方法降低來自於離散粒子效應產生的電場雜訊，藉此得到與理論符 合的線性朗道阻尼值，但電漿的非線性行為，例如相位捕獲(phase trapping)只能 使用足夠多的巨粒子模擬來降低結果的數值誤差。另外，我們使用Krook 形式碰 撞與正向碰撞兩種碰撞模型來模擬碰撞性電漿，我們會在本論文中探討離散粒子 效應如何去影響碰撞性電漿中的動力學行為。;The discrete-particle effects in particle-in-cell (PIC) simulation can numerically enhance the thermalization of collisionless plasmas, such that they can potentially change the dynamic properties of the simulated plasma system. The simulation results show that the numerical fluctuation induced by discrete-particle effects can be remedied by taking ensemble average over many computer runs to obtain the Landau damping rate, which is consistent with the theoretical estimation. But the nonlinear phase trapping can only be recovered from the numerical noise by using a reasonable number of macro-particle number in a Debye region. Moreover, both Krook-type and head-on collision models are implemented in the PIC simulation for studying the Landau damping in collisional plasmas. The convergence of numerical results due to discrete particle effects in PIC simulations will be discussed in the paper.
