Viscosity Measurements of Nitrogen and Argon at Temperatures from 90 K to 200 K and Pressures Up To 5 MPa

Accurate thermophysical properties will be essential to select and evaluate cryogenic fluids. The viscosity data of common cryogenic fluids was scattered below 200 K. To verify the data and reference correlations, in this work, the viscosity of nitrogen and argon in gas, liquid, and supercritical states were measured by using a vibrating-wire viscometer at temperatures between 90 K and 200 K and pressures between 0.3 MPa and 5 MPa. The standard uncertainty of the viscosity measurements was estimated to be 2.1 % over all temperature and pressure ranges. The results together with literature data were compared with the reference correlations. The results show good agreement between our measurements and those of the reference correlations within 2 %.