Measurement of a structured backflow in an open small channel induced by surface-tension gradients.

Alba Pulido-Companys, Josep Claret, Jordi Ignés-Mullol, Francesc Sagués

Departament de Química Física, Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Catalonia, Spain.

Physical review letters 2013 May 24

filter terms:

We present experiments in which the laterally confined flow of a surfactant film driven by controlled surface tension gradients causes the subtended liquid layer to self-organize into an inner upstream microduct surrounded by the downstream flow. The anomalous interfacial flow profiles and the concomitant backflow are a result of the feedback between two-dimensional and three-dimensional microfluidics realized during flow in open microchannels. Bulk and surface particle image velocimetry data combined with an interfacial hydrodynamics model explain the dependence of the observed phenomena on channel geometry.

Citation

Alba Pulido-Companys, Josep Claret, Jordi Ignés-Mullol, Francesc Sagués. Measurement of a structured backflow in an open small channel induced by surface-tension gradients. Physical review letters. 2013 May 24;110(21):214506