High-Pressure Binary Mass Diffusion Coefficients for Combustion Applications

A scaling for binary mass diffusion coefficients is developed using a corresponding states expression based on kinetic theory. The scaling is used to form nondimensional diffusion coefficients. Available data for high-pressure binary mass diffusion coefficients related to combustion applications are processed in conjunction with the scaling, leading to recommended scaled coefficient fits as a function of the reduced density. Data uncertainties and possible interpretation difficulties are examined. A means for comprehensive diffusion coefficient modeling over a broad (3 orders of magnitude) pressure range is suggested.