Experimental and Numerical Study of the Micromixer Using the Taylor-Dean Flow

(Effects of Aspect Ratio and Moving Wall on the Mixing)

Abstract

Chaotic mixing in six types of curved-rectangular channel flows has been studied experimentally and numerically. The wall of channel rotates around the center of curvature and a pressure gradient is imposed in the direction toward the exit of the channel. This flow is a kind of Taylor-Dean flow. We have investigated the effects of two different types of moving walls, inner and top walls (B.C.1), and an inner wall (B.C.2) on chaotic mixing. The non-dimensional parameters concerned are the Dean number De and the Taylor number Tr. The secondary flow is measured using PIV and LIF methods to examine secondary flow characteristics. Also we performed three-dimensional numerical simulations for the exactly same configuration as the experimental system to study the mechanism of chaotic mixing. It is found that good mixing is obtained in the case of De ≤ 0.1Tr. This tendency appears more strongly if the aspect ratio is large and B.C.1.