热阴极电离规灵敏度的数值模拟研究

Study on the Sensitivity of Hot Cathode Ionization Gauge by Numerical Simulation

本文基于数值模拟和实验方法研究热阴极电离规的计量性能,开展了电极电压和栅网结构对Bayard-Alpert电离规灵敏度的影响研究。研究表明,随着阴极阳极电压差从50 V增加到140 V,灵敏度持续增大,之后缓慢下降,随着栅网丝间距从2 mm增加到3.5 mm和丝径从0.4 mm减小到0.2 mm,灵敏度显著增大。采用正交分析法对电离规的结构和电压参数进行了优化,结果显示,当栅网丝径为0.2 mm,丝间距为3.5 mm,阳极电压为220 V,阴极电压为80 V时,热阴极电离规的灵敏度最大,模拟结果为0.184 Pa-1,根据优化和模拟结果进行了实验验证,实验结果为0.196 Pa-1,实验结果与模拟结果具有一致性。

Based on numerical simulation and experimental methods,the metrological performance of the hot cathode ionization gauge is studied,and the effects of electrode voltage and grid structure on the sensitivity of the ionization gauge are analyzed.The research shows that with the increase of cathode anode voltage difference from 50 V to 140 V,the sensitivity continues to increase and then decreases slowly.With the increase of grid wire spacing from 2 mm to 3.5 mm and wire diameter from 0.4 mm to 0.2 mm,the sensitivity increased significantly.The structural and electrical parameters of the ionization gauge are optimized by orthogonal analysis to improve the sensitivity.The results show that when the grid wire diameter is 0.2 mm,the wire spacing is 3.5 mm,the anode voltage is 220 V and the cathode voltage is 80 V,the sensitivity of the hot cathode ionization gauge is the largest.The simulation result is 0.184 Pa-1,the experimental verification is carried out according to the optimization results,the experimental result is 0.196 Pa-1.The experimental results are consistent with the simulation results.