Hydrodynamic repulsion of spheroidal microparticles from micro-rough surfaces

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Computational Science

Background:

• Isolating microparticles and cells is crucial for biomedical applications, especially in microfluidic devices handling blood.
• Understanding wall roughness effects on particle dynamics is essential for optimizing these systems.

Purpose of the Study:

• To theoretically investigate how micrometer-size wall roughness influences the mobility and dynamics of rigid microparticles in fluid flow.
• To quantify the impact of surface roughness on particle behavior in shear flow.

Main Methods:

• Utilized computer simulations combining the Lattice Boltzmann method for hydrodynamics.
• Employed the Lagrangian Particle dynamics method to model cell membrane dynamics.
• Quantified the effect of wall roughness on spheroidal microparticle mobility in shear flow.

Main Results:

• Wall roughness was found to significantly alter microparticle mobility.
• Mechanical and hydrodynamic interactions between particles and rough surfaces cause particles to lift off.
• The observed changes in mobility are sensitive to the specific shape of the microparticles.

Conclusions:

• Surface roughness plays a critical role in microparticle behavior within microfluidic systems.
• The findings provide insights into particle-wall interactions, essential for designing advanced biomedical devices.
• Particle shape is a key factor influencing the response to surface roughness.