Accurate improvement of a mathematical correlation for estimating diffusion coefficient in gaseous hydrocarbons

Abstract

Accuracy of Riazi-Whitson mathematical correlation for estimating the molecular diffusion coefficient in gaseous hydrocarbons has been improved, which decreases the absolute average deviation related to the experimental data using About 486 experimental data points that have been collected from latest existing researches. Likewise, re-optimizing, and statistical calculations have been done to synchronize data to avoid unexpected deviations. As shown in present work, deviation values for results of improved correlation from experimental data are less in compare to Riazi-Whitson original correlation. The absolute average deviations for obtained values of improved correlation are about 9.71%, which is about 14% for original mentioned correlation. The input parameters are molecular weight, critical properties, and acentric factors of components in the system; mixture molar density; low-pressure gas viscosity and actual viscosity. The last three properties are calculable by proper correlations in chemical handbooks.