Measurements of the viscosities of Kr and Xe by the two-capillary viscometry

Coiled two-capillary viscometers can measure gas viscosities with high accuracy over a wide temperature range. The authors built a two-capillary viscometer and used it to measure the zero-density viscosity of Kr and Xr at temperatures from 243.15 K to 393.15 K with relative standard uncertainties of 0.10% and 0.11%, respectively. Additional measurements on Ar were used to understand and avoid the error due to inadequate preheating or precooling...