Simulation and experimental study of asymmetric split and recombine micromixer with D‐shaped sub‐channels

Abstract

An effective passive micromixer based on the principles of asymmetric split and recombine has been designed, developed, and investigated to enhance the mixing performance of the micromixer in a microfluidic system. The effects of geometrical parameters and the number of mixing units on mixing performance were studied at different Reynolds (Re) number (ranging from 1 to 80) via CFD software ANSYS CFX. The results revealed that the preferable number of mixing units is 6, and the optimal direction of reducer is opposite to the main channel flow; the D-shaped mixing channel forces the mixed fluid to produce the extended vortex and Dean vortices simultaneously which caused a strong collision at the confluence of fluids, thus leading to the superposition and enhancement of the vortex system; when Re number is 80 and the width ratio of mixing channel W2/W3 = 1, the mixing efficiency of micromixer can exceed 95%.