title: Solutal convection in confined geometries: enhancement of colloidal transport.
abstract: We evidence experimentally and theoretically that natural convection driven by solutal density differences in a molecular binary mixture can boost the transport of colloids. We demonstrate that such buoyancy-driven flows have a negligible influence on the gradients that generate them, for moderate Rayleigh numbers in a confined geometry. These flows therefore do not homogenize the binary mixture but can disperse very efficiently large solutes. We illustrate the relevance of such effects thanks to several original experiments: drying of confined droplets, microfluidic evaporation, and interdiffusion in microfluidic flows.
authors.affiliation: Université Bordeaux, CNRS, Rhodia, LOF, UMR 5258, F-33680 Pessac, France.
authors.forename: B
authors.initials: B
authors.lastname: Selva
authors.forename: L
authors.initials: L
authors.lastname: Daubersies
authors.forename: J-B
authors.initials: JB
authors.lastname: Salmon