Modeling and Simulation of Dielectrophoretic Particle Assembly

Abstract

In this paper, we present a comprehensive study of dielectrophoretic particle assembly using hybrid immersed interface-immersed boundary method where both dielectrophoretic and hydrodynamic forces are evaluated with interface resolved approach instead of point-particle method. Immersed interface method is employed to capture physics of electrostatics in a fluid media with embedded particles, while immersed boundary method is used to study hydrodynamics with rigid and/or flexible immersed boundaries. Unlike existing studies, dielectrophoretic force is obtained using Maxwell’s stress tensor; a comparative study between Maxwell stress tensor and effective dipole moment methods are presented. This hybrid method is employed to demonstrate the dielectrophoretic particle assembly for both similar and dissimilar particles. In a fluid media, the similar particles form a chain parallel to the applied electric field, while the dissimilar particles form a chain perpendicular to the applied electric field. These results are consistent with the recent experimental observations.