ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

CFD-based optimization of an unbalanced electroosmotic micromixer

Ke Wang

School of Business, Chongqing Vocational College of Transportation, Chongqing, China

E-mail: vcpla2003@126.com

Received: 25 February 2025  Accepted: 15 April 2025

Abstract:

Micromixers are essential in microfluidic systems, with applications spanning multiple fields. This paper introduces an unbalanced electroosmotic microfluidic system, incorporating major and minor sub-channels with electrodes in the major channels. The finite element method is used to solve the governing equations, while the response surface method (RSM) optimizes the micromixer's performance. The study investigates how minor sub-channel size, electrode size and angle, inlet velocity (U_in), and applied voltage and frequency affect the mixing index (MI) and pressure drop (Δp). The findings indicate that MI increases with applied voltage and electrode angle, and also with inlet velocity. It is revealed that MI reduces and Δp increases with U_in. For instance, MI is reduced from 99.02 to 98.326% and Δp is enhanced from 4.66 to 18.380 kPa when U_in is raised from 1 to 7 mm/s. Optimal values are determined for applied frequency and electrode radii. Six independent variables are chosen to optimize the micromixer by maximizing MI and minimizing Δp, leading to two correlations proposed via RSM for MI and Δp. The proposed micromixer is versatile and suitable for various applications such as biomedical diagnostics, chemical synthesis, and biochemical analysis.

Keywords: Chemical Process Engineering; Chemical Engineering; Engineering Fluid Dynamics; Fluidics; Microfluidics; Nanofluidics; Microfluidics; Unbalanced micromixer; Electroosmotic micromixer; Mixing index; Optimization

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04070-z

Chemical Papers 79 (7) 4471–4486 (2025)