Viscosity of CHF3 in the critical region

The gaseous viscosity of trifluoromethane [CHF3) was measured in the critical region. The experimental temperature range was between 299.150 and 303.150 K and the pressure range was up to 5.66 MPa. The measurements were obtained with an oscillating-disk viscometer, combined with local determination of the density at the position of the oscillating disk, and they have an estimated accuracy of 0.6 % for the viscosity and 0.5 % for the gas density. The viscosity of CHF3 exhibits an anomalous increase near the critical point. The anomalot, s increase in viscosity was analyzed with the viscosity equation proposed by Basu and Sengers.