基于偏微分弱形式方程的棒-板短空气间隙流注放电仿真

Simulation on Streamer Discharge of Short Rod- Plane Air Gap Based on Weak Form Equations of PDE

随着计算机运算能力的迅速提升,采用数值仿真方法研究气体放电过程已成为热点。根据气体放电理论推导的流体动力学模型,属于对流占优方程,求解计算存在数值振荡和数值扩散问题。文中采用加权余量法的伽辽金弱形式求解该模型,仿真了棒板10mm空气间隙的流注放电过程。仿真结果表明:电子﹑正离子在流注发展过程中的浓度为1016cm-3数量级,负离子为1015cm-3;电子碰撞电离占主导作用,空间电荷对电场分布有明显的畸变作用;数值振荡和数值扩散得到了有效消除。

With the rapid increase of computing power,the use of numerical simulation method of gas discharge process has become a hot spot. Numerical oscillation and numerical diffusion issues exist in solving hydrodynamic models derived from gas discharge theory,which belongs to convection- dominant equation. In this paper,the Galerkin weak form of weighted residual method is used to solve the model,and the streamer discharge process in a 10 mm rod- plate air gap is simulated. Simulation results show that the electron and positive ion＇s concentration in the streamer discharge process are both at the order of magnitude of 10^16cm- 3,and negative ion＇s is at 10^15cm- 3.Therefore,electron impact leads ionization,and the space charge has obvious distortion effect on electric field distribution.By this way the numerical oscillation and numerical diffusion are effectively eliminated.