Experimental Comparative Mixing Performance and Pressure Drop Simulation of Three Passive Micromixers

This paper describes an experimental investigation of the mixing performance in three different geometries: T-micromixer, O-micromixer and a new type of passive microfluidic mixer called the “H-micromixer”. This type of passive micromixer is based on the SAR process, meaning that the two fluids to be mixed are split and recombined to optimize the diffusion process due to the H-shaped sub-channel. The paper also describes a numerical simulation of the pressure drop in three different geometries. The laminar flow regime (0.08 < Re < 4.16) was considered during tests and image-based techniques were used to evaluate mixing efficiency. At all tested flow rates, experimental data show that the H-micromixer is more efficient and also numerical simulation illustrate that H-micromixer has a greater pressure drop than the other tested microdevices. The H-micromixer’s efficiency is very high due to the SAR process: specifically, efficiency up to 98% can be achieved at Re=0.083 and also pressure drop is 2.19 Pascal at this Reynolds number