In the conventional mass transfer analysis in binary mixtures, a constant total mass concentration (or density) in the mass transfer layer has been assumed. This assumption is valid only once the concentration of diffusing component in the mixture is very low. Here, an explicit is introduced for the density within the mass transfer layer in order to see what happens when the conventional composition-independency assumption for the density within the mass transfer layer is relaxed. The governing equations are derived analytically and solved numerically. It was found that the conventional approach is a special case of our newly proposed composition-dependent density profile. While application of conventional approach is limited to very dilute binary mixtures, newly approach is applicable to general binary mixtures.

中文翻译：

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关于传质层内密度的成分依赖性的注释


在二元混合物中的传统传质分析中，假设传质层中的总质量浓度（或密度）恒定。仅当混合物中扩散组分的浓度非常低时，该假设才有效。这里，引入了传质层内密度的显式，以便了解当放宽传质层内密度的传统组成独立性假设时会发生什么。控制方程通过解析导出并通过数值求解。结果发现，传统方法是我们新提出的依赖于成分的密度分布的特例。虽然传统方法的应用仅限于非常稀的二元混合物，但新方法适用于一般的二元混合物。