Mesoscopic electrohydrodynamic simulations of binary colloidal suspensions

Area of Science:

• Computational physics
• Fluid dynamics
• Colloid science

Background:

• Electrokinetic phenomena are crucial in colloidal suspensions.
• Existing models often lack integrated simulation of hydrodynamics, electrokinetics, and colloid behavior.

Purpose of the Study:

• To develop and validate a comprehensive computational model for electrokinetic phenomena in colloidal suspensions.
• To enable the simulation of complex fluid-solute-colloid interactions.

Main Methods:

• Lattice Boltzmann method for binary fluid flows with a Bhatnagar-Gross-Krook collision operator.
• Pseudopotential model for fluid-fluid and fluid-solute interactions.
• Finite difference discretization of the Nernst-Planck equation using the link-flux method.
• Coupling of colloids to hydrodynamics and electrokinetics via boundary conditions.

Main Results:

• Successful integration of discrete Boltzmann equation, Nernst-Planck equation, and colloid dynamics.
• Validation against analytical solutions for ionic distributions, droplet deformation, and electrophoretic mobility.
• Demonstration of model's capability in simulating droplet breakup and interfacial colloidal dynamics.

Conclusions:

• The presented model offers a unified framework for simulating electrokinetic phenomena in complex fluid mixtures.
• This integrated approach advances the understanding of colloidal behavior in various fluid interfaces and dynamic systems.
• The validated model opens new avenues for exploring charged and neutral droplet dynamics and interfacial colloidal transport.