Optimization Design of a Novel Passive Micromixer Using Response Surface Methodology

Biochips and microchemical systems utilize micromixers to mix various reactants in microscale environments effectively. The innovative microfluidic device is described. This study aims to enhance the Mixing Index (MI) by changing geometric parameters and inlet velocity. This micromixer consists of two unbalanced U-shaped channels connected by a chevron obstacle within a hexagonal mixing chamber, which promotes efficient fluid interaction. Numerical simulations are performed using the finite element-based COMSOL Multiphysics software, and the results are used to optimize the micromixer performance using Response Surface Methodology (RSM). It is found that the inlet velocity greatly affects the MI and pressure drop (Δp), whereas the angle between the inlets does not affect either of these parameters. For instance, MI increases from 80.85% to 94.52% when Uin is raised from 0.01 m/s to 1 m/s. In general, the suggested micromixer exhibits an MI higher than 80% for all ranges of the considered independent variables. Furthermore, two correlations for MI and Δp are provided by the RSM that can be used to maximize this micromixer's performance.