Viscosities of oxygen and air over a wide range of temperatures

Abstract

Measurements have been made of the viscosities of oxygen and air relative to that of nitrogen in the temperature range 120–1620 K using capillary flow methods over a range of gas pressures. Concurrent measurements of the viscosity of argon served as a check on the methods and on the standards of viscosity adopted. The calculation of various correction factors, which convert the measured gas flow times to accurate viscosity ratios, is discussed. A room temperature nitrogen standard, based on the air standard of Bearden, together with standard viscosities obtained over a wide range of temperature by Clark, Gough and Dawe, are used to obtain viscosities for each gas which are estimated to be accurate to ±0.5 %, rising to ±1.0 % above 1000 K and ±1.5 % below 200 K. The viscosities are compared with those of previous workers and also with the smoothed values proposed by Maitland and Smith and by Watson.