棒-板电极下缩比气隙辉光放电相似性的仿真研究

建立了棒-板电极下氩气直流放电的流体模型,利用有限元法对几何位形相似的两个气隙放电过程进行了数值求解.两放电气隙外加电压相同,气隙线性尺寸的比值为10:1,气压分别为1 Torr和10 Torr.仿真得到了两相似气隙的放电的伏安特性曲线以及放电物理量(如电位、电场、电子密度、离子密度、电子温度等)的空间分布.根据气体放电相似性的基本结论,检验了气隙对应物理量之间的数值关系.结果表明:两相似气隙的放电类型为正常辉光放电,对应放电物理量之间存在相似性理论指出的比例关系,且在相同幅值的直流电压作用下,气隙放电的工作点相同.这将为利用气体放电相似性来外推相似气隙的放电特性提供一定的理论依据.

Simulation on similarity law of glow discharge in scale-down gaps of rod-plane electrode configuration

A fluid model of direct-current (DC) discharge in argon atmosphere between the gaps of rod-plane electrode configuration was established, and the discharge models of two geometrically similar gaps were solved using the finite-element method, respectively. The dimension ratio of the gaps was set as 10:1, and the gas pressure was ～133.3 Pa for the prototype and ～133 Pa for the scale-down gap; to the gaps the same DC voltages were applied. Voltage-current characteristics, as well as the physical discharge parameters (such as electric potential, electric field, electron density, ion density, and electron temperature) were obtained. Relations between parameters of the two gaps were investigated according to the theoretical relations derived by similarity law. Simulation results show that the discharge type in the two similar gaps is verified as a normal glow discharge; the parameter relations are in good agreement with the similarity law, and the working points of discharges are identical in similar gaps with the same applied DC voltage. This study could offer theoretical instruction in extrapolating the discharge properties for similar gaps.
Keywords： discharge similarity glow discharge rod-plate electrode scale-down gap