The negative corona discharge between a small spherical metal electrode (SSME) and a grounded plane electrode (GPE) was often a concern. The ring mode discharge and the dot mode discharge were found in the experimental study. Up until now, these two phenomena are not verified in simulation study. Simulation on the negative corona discharge between an SSME and a GPE is staged in this article. The pulse currents in negative corona discharge are analyzed under different voltages, radius of the SSME, and gap distance coupling fluid dynamic equations and Poisson equation based on the axisymmetric model. The interesting phenomenon found is that the corona discharges sequentially happen at different central angles on the surface of the SSME starting with the point nearest to the GPE. The negative corona discharges generated by the SSME and the hemispherical metal electrode are compared. The mechanism of discharge is analyzed by comparing their current pulses, electric field intensities, and changes in the concentration of ions. The ring mode discharge and the dot mode discharge are shown in our simulation. The reason for the formation of the ring mode discharge is also given.

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小球形金属电极负电晕放电的研究

小型球形金属电极 (SSME) 和接地平面电极 (GPE) 之间的负电晕放电通常是一个问题。在实验研究中发现了环模放电和点模放电。到目前为止，这两种现象都没有在模拟研究中得到验证。本文对 SSME 和 GPE 之间的负电晕放电进行了模拟。基于轴对称模型的不同电压、不同SSME半径、间隙距离耦合流体动力学方程和泊松方程对负电晕放电脉冲电流进行了分析。发现的有趣现象是，从最靠近 GPE 的点开始，在 SSME 表面的不同中心角处依次发生电晕放电。比较了 SSME 和半球形金属电极产生的负电晕放电。通过比较它们的电流脉冲、电场强度和离子浓度的变化来分析放电机制。我们的模拟显示了环形模式放电和点模式放电。还给出了形成环模放电的原因。