Experimental comparative mixing performance of passive micromixers with H-shaped sub-channels

This paper presents a new type of passive microfluidicmixer called the ‘‘H-micromixer’’.This type of passive micromixeris based on the splitting and recombination (SAR)process, meaning that the two fluids to be mixed are split and recombined to optimized the diffusion process.The paperalso describes an experimental investigation of the mixing process in three different geometries:T-micromixer,O-micromixer and H-micromixer. The laminar flowregime(0.08<Re<4.16)was considered during tests and image-based techniques were used to evaluate mixing efficiency.At all tested flowrates, experimental data show that the H-micromixer is more efficient than the other tested microdevices.The H-micromixer’s efficiency is very high due to the SAR process: specifically,efficiency up to 98%can beachieved at Re=0.083.