中文摘要：

为了研究缩比实验在气体放电中的有效性,对缩比间隙中的低气压氩气放电进行了数值模拟.根据气体放电相似性的猜想,如果间隙气压 p和间隙距离d 的乘积为常量,即 p1d1=p2d2,并且约化电场E/p在两个间隙中的空间分布相同,那么这两个放电间隙的放电特性存在相似性.数值模拟中设置三个缩比间隙：气隙A的长度为30 mm,气压为1 Torr （1 Torr=133.322 Pa）；气隙B的长度为15 mm,气压为2 Torr；气隙C的长度为10 mm,气压为3 Torr.仿真结果表明,三个间隙均为辉光放电,并存在明显的阴极位降区.间隙A, B, C的阴极位降区的厚度dC分别为2.71,1.35和0.87 mm,相对应的pd值几乎相同,即pdC≈2.70 Torr·mm.这与氩气辉光放电Paschen曲线最低点（ pd≈2.86 Torr·mm）相近.缩比间隙的放电参数的特性（如工作电压、电场、电流密度、电子密度和离子密度的沿“空间”px的分布）的数值计算结果与放电相似性猜想所预计的结果一致.所以,可以认为放电相似性猜想适用于低气压氩气缩比间隙的辉光放电.

英文摘要：

In order to investigate the validity of the scale-down experiment on gas discharge, the discharge in argon at low pressure is numerically simulated with scale-down discharge gap based on the conjecture of discharge similarity that if the product of gas pressure p and gap length d is kept constant, p1d1=p2d2, and the spatial distributions of the reduced field E/p along these two gaps are the same, the gas discharges in these two discharge gaps would be similar. In the simulation, three scale-down discharge gaps are used. Gap A is 30 mm long and works at a pressure of 1 Torr （1 Torr=133.322 Pa）. Gap B is 15 mm long at 2 Torr and gap C 10 mm long at 3 Torr. The results show that the discharges in these three gaps are glow discharges with a cathode fall layer. The values of thickness of the cathode fall layer, dC, for gaps A, B and C are 2.71 mm, 1.35 mm and 0.87 mm, respectively, which corresponds to more or less the same value of pdC≈2.70 Torr·mm that is close to the lowest point of Paschen curve of argon where pd≈2.86 Torr·mm. The proportionalities of the parameters （working voltage, electric field, current density, electron density and ion density） between the discharges in the scale-down gaps are found to be in good agreement with those determined by the discharge similarity. It is concluded that the conjecture of discharge similarity is correct for the glow discharge in argon in the scale-down gap.