%A DENG Qiangguo,, SONG Pengyun, MAO Wenyuan, XU Hengjieª¤ %T Fitting expression of relationship gas viscosity, and temperature and/or pressure %0 Journal Article %D 2017 %J Journal of Drainage and Irrigation Machinery Engin %R 10.3969/j.issn.1674-8530.16.0033 %P 144-151 %V 35 %N 2 %U {http://zzs.ujs.edu.cn/pgjx/CN/abstract/article_2189.shtml} %8 2017-02-25 %X Gas viscosity is an important parameter for the performance of gas lubrication mechanism such as dry gas seal. The gas viscosity is related to temperature and pressure under the condition of high pressure, but there are few researches about the detailed relations between viscosity, temperature and pressure. Nitrogen(N2)is taken as the study object, and the viscosity-temperature fitting expression and the viscosity-pressure fitting expression, the viscosity-temperature-pressure fitting expression have been obtained based on the AP1700 material physical platform using the least square method by a mathematic software. The calculated results by the fitting expressions have enough accuracy compared with the viscosity values offered by the National Institute of Standards and Technology(NIST)Chemistry WebBooks, China national standard Heat Exchangers(GB/T 151-2014), calculated values in Booser¡äs publication Tribology Data Handbook respectively and calculated values by the Lucas equation. The results show that the fitting expressions can be used to express the changing laws of gas viscosity with temperature and pressure and to calculate the viscosity concerning the temperature and/or the pressure.ª¤