Topology Optimization of Passive Micromixers Based on Lagrangian Mapping Method

Area of Science:

• Fluid Dynamics
• Microfluidics
• Chemical Engineering

Background:

• Passive micromixers are crucial for efficient mixing in microfluidic devices.
• Designing micromixers for immiscible fluids, especially under convection-dominant conditions (infinite Peclet number), presents significant challenges.
• Existing topology optimization methods often use Eulerian descriptions, which are less suitable for convection-dominated scenarios.

Purpose of the Study:

• To develop an optimization-based design method for passive micromixers specifically for immiscible fluids.
• To address the extreme case where convection dominates mixing, with negligible diffusion.
• To find the optimal layout of passive micromixers for enhanced performance.

Main Methods:

• Utilizing a topology optimization method to construct an optimization model.
• Employing the mapping method, a Lagrangian description, to model mixing dynamics.
• Focusing on convection-dominated flow regimes, distinct from Eulerian-based convection-diffusion models.

Main Results:

• Demonstrated the validity of the proposed optimization-based design method through numerical examples.
• Successfully modeled mixing dynamics in the extreme case of convection dominance.
• Provided a framework for designing optimal passive micromixer layouts.

Conclusions:

• The proposed method offers an effective approach for designing passive micromixers for immiscible fluids under convection-dominant conditions.
• The mapping method is well-suited for modeling mixing dynamics in such extreme scenarios.
• This optimization-based design strategy advances the field of microfluidic device engineering.