Electrothermal blinking vortices for chaotic mixing

P. Kauffmann, S. Loire, I. Mezic
UCSB, US

Keywords: mixing, blinking vortices, electrothermal flows, electrokinetics

Summary:

At microscale, an efficient mixing is a keystep which dramatically accelerates bio-reactions. This paper presents an experimental and theoretical study of electrothermal chaotic mixing. To do so, asymmetric vortices are blinked to perform time dependant velocity flows. Successive horizontal plans of velocity are measured at different heights by micro particle image velocimetry microPIV. Electrothermal flows are modeled with 2D finite element method using COMSOL multiphysics software. The velocity profile experimentally reconstructed shows a dramatic asymmetry between the two vortices, in good agreement with the FEM model. The mixing of two fluids are studied. The blinking vortices method dramatically increase mixing efficiency.