Experimental study on the performance of a mini-scale Y-type mixer with two liquid metal-enabled pumps

Abstract

The mixing process of two liquids inside an open minichannel was experimentally studied in the presence of liquid metal and an electric field. The Y-type mixers under study were made of Plexiglas, and two liquid metal-enabled pumping systems (based on electrically induced surface tension gradients) were placed at the inlets of the mixer instead of conventional syringe pumps. The effects of the mixing angle, the voltage applied to the liquid metals, and the Reynolds number on the mixing process were investigated. To accurately determine the mixing index, the image processing toolbox of MATLAB software was employed. The results showed that the mixing intensity increased as the applied voltage signal increased, thereby creating a chaotic advection in the minichannel. Furthermore, although the Reynolds number of induced flow and the applied voltages were directly proportional, the input angle plays an important role in the mixing. Among the considered models, in the constant voltage, the 30° and 90° had the best and the worst mixing, respectively. The maximum mixing intensity of 94% was obtained at an input angle of 30° and voltage of 14 V, where, in the absence of an electric field, the maximum mixing intensity was 55%.