New Jersey Institute of Technology
Particles suspended in a fluid and subjected to an electric field exhibit motion when the particles and the fluid have different electrical properties. Such motion, referred to as "dielectrophoresis", has recently attracted much attention for the controlled manipulation and separation of micrometer and submicrometer-sized particles such as biological cells, microorganisms and macromolecules. Despite numerous applications ranging from biotechnology to materials processing, the development of this field into new technologies has been hindered by our lack of understanding of the various physical phenomena involved. In this presentation, we propose novel direct simulations of electro-rheological suspensions based on the Distributed Lagrange Multiplier method (DLM) in which the flow-particle interactions are accounted for exactly, and the mutual electrostatic forces acting on the polarized particles are represented by means of the point-dipole approximation. Numerical simulations will be presented for both uniform and spatially varying electric fields in the case of imposed and no imposed flow, and compared with experimental results.