Experimental study on the conductance of pure and binary gas mixtures

• Published in: Vacuum 2021-07, Vol.189, p.110277, Article 110277
• Main Authors: Wei, Ningfei, Feng, Yan, Sun, Wenjun, Cheng, Yongjun, Dong, Meng, Song, Yi, Wu, Chengyao, Liu, Guoting, Qiu, Yuntao
• Format: Article
• Language: English
• Subjects: Binary gas mixture; Conductance; Equivalent single gas method; Pure gas
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2021.110277

A binary gas mixture conductance measurement apparatus with an independent gas distribution system was established, the constant volume method to measure the conductance of the mixed gas was used. Also, the conductance of pure gas Ar, He, N2 and binary gas mixtures Ar–He, N2–He, Ar–N2 through a short tube under different gas distribution chamber pressures and different molar fractions were measured. Meanwhile, the equivalent single gas method was used to calculate the conductance of binary gas mixtures. To verify the accuracy of this method, the relative error between the calculated and the measurement was carried out. The result shows that the equivalent single gas method is suitable for a small Knudsen number (1/Kn≥10), the molar fraction of lighter species is low and a small difference in the molecular mass of the components in the mixed gas. The uncertainty of conductance measurement is better than 3.1%. •A binary mixed gas conductance measurement apparatus with an independent gas distribution system was established.•The conductance of binary mixed gas at different G-D chamber pressures and different molar fractions was measured.•The equivalent single gas method was used to calculate the conductance of binary gas mixture.