Viscosity modeling of light gases at supercritical conditions using the friction theory

The viscosities of argon, helium, hydrogen, krypton, methane, neon, nitroge n, and oxygen have been modeled using the friction theory (f-theory) for vi scosity modeling in conjunction with the Peng-Robinson (PR) equation of sta te (EOS), Soave-Redlich-Kwong EOS, Stryjek-Vera modification of the PR EOS, and Mathias modification to the SRK EOS. The viscosity modeling has been p erformed at supercritical conditions and up to 1000 bar, covering most comm on conditions in industrial processes. The overall average absolute deviati on for each fluid ranges from 0.4 to 1.4% and is in excellent agreement wit h the reported uncertainty of the recommended literature values. These resu lts are obtained using only three friction constants and without any knowle dge of the density. Further it has been found that the dilute gas viscosity can also be modeled using only three constants for each fluid, from the cr itical temperature up to 2000 K, within or close to the uncertainty of the recommended dilute gas viscosity data. The obtained results further show th e application of the f-theory for viscosity modeling and its potential for applications to industrial processes.