摘要
利用粒子输运方程及耦合泊松方程,研究了短间隙中10%~90%SF_6/N_2混合气体在不同阶段的流注放电特性。针对流注头部粒子空间分布出现陡梯度问题,基于不均匀的三角元网格剖分,采用Euler-Taylor-Galerkin(ETG)格式对粒子连续性方程进行时间离散,利用通量校正传输法(FCT)对离散后的方程进行求解,可以明显提高计算准确度和减小数值扩散。基于以上算法,考虑电子与SF_6/N_2中性混合气体的电离、复合、吸附以及光电离等过程,对短间隙气体流注放电过程进行了仿真。仿真结果表明,初始场强的大小影响流注的发展,随着流注发展,流注头部空间电荷加剧了两极板间的电场畸变,间隙击穿时流注头部电子浓度达到10^(20)/m^3,最大空间场强达到114k V/cm;光电离对加速流注的形成和发展有很大的影响;仿真结果也验证了ETG-FCT法应用于气体放电研究的有效性。
The characteristics of short gap streamer discharge at different stages in 10%-90% SF6/N2 gas mixtures are simulated using particle transport equation and coupled Poisson equation. The spatial distribution of particles in streamer head appears steep gradients. To improve the computing efficiency and reduce numerical diffusion, the non-uniform triangular element mesh method is introduced. The temporal discretization of particle continuity equation is solved by the Euler- Taylor-Galerkin scheme （ETG） discrete, while the discrete equations are solved by the flux corrected transport （FCT） method. In the process of simulation, ionization, recombination, attachment and photoionization are considered in SF6/N2 mixed gas. The electric field intensity between anode plate and cathode plate changes a lot with the electric field distortion by space charge distribution as streamer propagation. The initial condition of streamer discharge of short gap breaks down. The electron concentration of the streamer head is about 10^20/m3, and the electric field value in the streamerhead is about 114kV/cm. The results show that the photoionization has great influence on streamer formation and propagation, and prove that the ETG-FCT method is valid
出处
《电工技术学报》
EI
CSCD
北大核心
2016年第6期234-241,共8页
Transactions of China Electrotechnical Society
基金
教育部新世纪优秀人才支持计划基金项目(NCET-11-0130)
高等学校博士学科点专项科研基金(20120161110009)资助
