Computational inertial microfluidics: a review.

Area of Science:

• Microfluidics
• Computational Fluid Dynamics (CFD)
• Particle Migration

Background:

• Inertial focusing, discovered in 1961, describes particle migration in fluid flows, but a complete theoretical understanding remains elusive.
• Computational approaches are increasingly used to elucidate the physics of particle focusing in microfluidic devices.
• Existing theories often lack comprehensive explanations for particle behavior across various conditions.

Purpose of the Study:

• To review and categorize numerical models for simulating inertial particle motion in microfluidics.
• To provide a framework for selecting appropriate numerical solutions for diverse particle and fluid types.
• To highlight key aspects of particle focusing in straight and curved microchannels.

Main Methods:

• Categorization of models into semi-analytical, Navier-Stokes-based, and lattice Boltzmann methods.
• Detailed exploration of particle focusing dependence on particle size, channel geometry, and Reynolds number.
• Inclusion of general equations, tutorial appendices, and numerical study details for reader engagement.

Main Results:

• Analysis of how different computational models address inertial particle migration.
• Identification of factors influencing particle focusing, including channel shape and flow characteristics.
• Discussion of model applicability to deformable/rigid, spherical/non-spherical particles in Newtonian/non-Newtonian fluids.

Conclusions:

• Numerical modeling is essential for understanding inertial particle motion in microfluidics.
• A clear differentiation between modeling approaches aids in selecting suitable methods.
• Future research should address remaining challenges in modeling inertial particle microfluidics.