Development of mass-producible rapid mixer based on baker's transformation

Abstract

We developed a new passive-type lamination mixer for high viscosity fluid with a low Reynolds number, based on the baker's transformation (BT). BT is the best transformation for mixing fluids of laminar flow. However, there was difficulty in mass-producing the BT structure especially for micro devices like MicroTAS, Lab-on-a-Chip and Micro-Reactors, because conventional BT mixers require three-dimensional (3D) piping structures. We have successfully developed the easy-to-massproduce BT mixer by changing that concept of 3D piping structures to 3D channel structures. The 3D channel structures are not easy to produce by photolithography unlike the conventional mixers, while they can be easily mass-produced by molding once their 3D molds are produced. In this report, we newly developed a miniature scale BT mixer to meet the needs for mixing high viscosity fluids in food processing, resin blending, etc. An experiment for mixing different colored hardening silicone elastomers was performed by using the prototype mixer made of aluminum alloy, and the good BT mixing result was obtained, with observing several cross sectional patterns. The numerical fluid analysis also gave similar results of the patterns to those observed in the experiment. © 2012 The Japan Society of Mechanical Engineers.