Title :
Modeling of conductive particle behavior in insulating fluids affected by DC electric fields
Author :
Dascalescu, Lucian ; Mihailescu, Michaela ; Tobazéon, Robert
Author_Institution :
Lab. d´´Electrostatique et de Mater. Dielectriques, CNRS, Grenoble, France
Abstract :
Several electrostatic technologies, such as separation of granular mixtures, flocking, printing, or biological cell manipulation, are based on the accurate control of conductive particle motion in insulating gases or liquids by means of relatively high DC electric fields. This paper is aimed at characterizing the behavior of such particles by numerical modeling of two aspects: (1) particle motion under the action of electric field forces and (2) insulation breakdown triggered by mobile particles. The equations of particle motion were written by taking into account both gravitational and drag forces, as well as the rebound at particle impact with the electrodes. If the particles move in ionized air, their charge varies in time. In that case, the equation of particle charge should be added to the mathematical model. The output data of the programs for numerical simulation of particle behavior are in good agreement with the available experimental results. Particle movements were shown to be influenced by the intensity of the electric field, by the density of the space charge, by size and mass density of the particles, as well as by their coefficient of restitution at impact with the electrodes. The conclusions regarding the behavior of conductive particles in insulating fluids are useful for the development of improved electrostatic separation technologies; they are of particular interest to all manufacturers of high-voltage equipment
Keywords :
conducting materials; electric breakdown; electric fields; electrostatic devices; electrostatics; insulating oils; biological cell manipulation; coefficient of restitution; conductive particle behavior; corona; drag forces; electric field forces; electrostatic separation; electrostatic technologies; flocking; granular mixtures separation; gravitational forces; high DC electric fields; high-voltage equipment manufacturers; insulating fluids; insulation breakdown; ionized air; mass density; mobile particles; particle motion; printing; space charge density; Biological cells; Biological control systems; Biological system modeling; Dielectrics and electrical insulation; Electrodes; Electrostatics; Equations; Gas insulation; Motion control; Printing;
Journal_Title :
Industry Applications, IEEE Transactions on