Analytic modelling of passive microfluidic mixers.

Area of Science:

• Microfluidics
• Computational Fluid Dynamics
• Analytical Modeling

Background:

• Existing microfluidic passive mixer models include physics-based advection-diffusion-reaction equation (ADRE) simulations and electronic-equivalent circuit models.
• ADRE simulations are accurate but computationally intensive, while electronic-equivalent models simplify analysis but assume fluid homogeneity, limiting their applicability.

Purpose of the Study:

• To develop a novel analytical model for microfluidic passive mixers that bridges the gap between physics-based accuracy and computational efficiency.
• To integrate ADRE-derived insights into electronic-equivalent models, accounting for concentration gradients perpendicular to the flow.

Main Methods:

• Derivation of an analytical model from the advection-diffusion-reaction equation (ADRE) under specific assumptions.
• Integration of the derived analytical model into existing electronic-equivalent circuit frameworks.
• Validation against finite element simulations using COMSOL Multiphysics across various scenarios.

Main Results:

• The new analytical model accurately predicts microfluidic mixer performance, capturing concentration gradients.
• The model demonstrates a global error of less than 5% when compared to finite element simulations.
• Significant reduction in computational resource requirements compared to traditional ADRE-based simulations.

Conclusions:

• The developed analytical model offers a computationally efficient and accurate alternative for microfluidic passive mixer analysis.
• The model's compatibility with simulation languages like SPICE and Verilog-AMS facilitates in silico prototyping of complex microfluidic and lab-on-chip devices.