N(adsbygoogle = window.adsbygoogle || []).push({}); _{A}= J_{A}^{*}+ C_{A}*(N_{A}+N_{B})/C for a binary mixture.

NBut I don't see why this is the case. I don't see why N_{A}is the flux of the fluid relative to a stationary point.

J_{A}^{*}is Fick's law, the flux relative to the bulk motion of the fluid?

(N_{A}+N_{B})/C is the bulk velocity of the fluid.

_{B}should affect N_{A}at all. For example, for an ideal gas, the molecules of component B should have no impact on the motion of the molecules of component A. I (think I) understand the need for accounting for a moving reference frame, but it doesn't make sense to me that if we had a hypothetical situation where A is concentrated initially at a small volume, and somehow we were able to make all of the "B" molecules move in some direction, that this would affect N_{A}. An explanation or clarification would be appreciated!

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# Fick's Law and the Diffusion/Convection combined equation.

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