Constancy of the Dynamic Viscosities of Ternary Gas Mixtures

摘要

The dynamic viscosities of ternary gas mixtures oxygen-nitrogen-carbon dioxide and hydrogen-nitrogen-oxygen are investigated. Starting from Wilke's equation for the prediction of the viscosities of gas mixtures whose volumetric analysis is known, it is shown that in the case of oxygen-nitrogen-carbon dioxide mixture the viscosity at a particular temperature remains constant irrespective of the percentage of nitrogen present in the mixture as long as the volumetric ratio of oxygen to carbon dioxide in the mixture is maintained at 11 to 8. This has been verified experimentally by the oscillating disc viscometer. Theoretical calculations based on Wilke's equation show that when the ratio of hydrogen to oxygen is 2 to 1 in a tenary mixture of hydrogen-nitrogen-oxygen, the viscosity of the mixture at a particular temperature is constant irrespective of the percentage volume of nitrogen present. The viscosity and molecular weight of nitrous oxide is equal to that of carbon dioxide. It is possible to replace carbon dioxide by nitrous oxide in a mixture of oxygen-nitrogen-carbon dioxide without affecting the final viscosity of the ternary mixture. Similarly, carbon monoxide can replace nitrogen in a mixture of hydrogen-nitrogen-oxygen. (Author)