Assumed having axial symmetry, the streamer discharge is often described by afluid model in cylindrical coordinate system, which consists of convectiondominated (diffusion) equations with source terms, coupled with a Poisson'sequation. Without additional care for a stricter CFL condition or specialtreatment to the negative source term, popular methods used in streamerdischarge simulations, e.g., FEM-FCT, FVM, cannot ensure the positivity of theparticle densities for the cases in attaching gases. By introducing thepositivity-preserving limiter proposed by Zhang and Shu \cite{ppl} and Strangoperator splitting, this paper proposed a finite difference scheme with aprovable positivity-preserving property in cylindrical coordinate system, forthe numerical simulation of streamer discharges in non-attaching and attachinggases. Numerical examples in non-attaching gas (N$_2$) and attaching gas(SF$_6$) are given to illustrate the effectiveness of the scheme.
展开▼
机译：假定具有轴向对称性，通常由圆柱坐标系中的流体模型来描述拖缆的排放，该模型由具有源项的对流占优（扩散）方程和泊松方程组成。如果没有对更严格的CFL条件进行特殊照顾或对负源项进行特殊处理，则在流光放电模拟中使用的流行方法（例如FEM-FCT，FVM）无法确保附着气体的情况下颗粒密度的正值。通过引入Zhang and Shu \ cite {ppl}提出的正保持性限制器和Strangoperator分裂方法，提出了一种在圆柱坐标系中具有可保持正性的有限差分方案，用于非附着气体和附着气体中流光放电的数值模拟。 。给出了非附着气（N $ _2 $）和附着气（SF $ _6 $）的数值示例，以说明该方案的有效性。
展开▼
