Convective diffusion from strip-like micro-probes into colloidal suspensions

Full equations of convective diffusion are solved numerically for a strip-like (2D) electrodiffusion friction probe in a stream of microdisperse liquid, assuming a non-linear near-to-wall velocity profile ranging from simple shear flow (p = 1) to ideal slip (p = 0). The range of generalized Peclet number H from H = 0.01 (almost pure spatial diffusion) to H = 100 (diffusion layer with negligible longitudinal diffusion) covers all cases of possible experimental relevance. The main result is expressed as a relative deviation of actual total diffusion flux N from its diffusion-layer approximation NDLA, Ψ = N/NDLA − 1.