Experimental and numerical assessment and performance optimization of a novel T-arrow microfluidic device to mix two fluids with different thermophysical properties

Abstract

Micromixers are critical parts of integrated microfluidic systems and their performance improvement has been a crucial problem for many investigators. Since the mixing enhancement in passive micromixers is hindered by the low-Reynolds number regime, multiple inlets have been recommended to create chaotic advection and improve the mixing quality. In this paper, a novel T-arrow micromixer is introduced to augment the mixing index (MI) of two liquids with different thermophysical properties. Numerical and experimental investigations are carried out by changing the distance between the inlets (a), the angle of the arrow-shaped inlet (α), the velocity ratio (VR), and the width-to-height aspect ratio (AR). Five optimization algorithms are also utilized to optimize the micromixer performance to achieve the most appropriate geometrical characteristics. It is found that MI is enhanced significantly by adding a Y-type inlet compared to a T-shaped mixer. The results demonstrate that while MI declines with a, there are optimal values for α, VR, and AR. Besides, parallel optimization of MI and pressure drop recommends two optimal micromixers with mixing energy cost (MEC) of 2841 Pa and 3370 Pa.