Particle electrification and levitation in a continuous particle feed and dispersion system with vibration and external electric fields

Abstract

Electrification and levitation of particles in a continuous particle feed and dispersion system have been studied both theoretically and experimentally. This system consisted of a vibrator and inclined parallel electrodes. A mesh and a vibrating plate were used for the upper and lower electrodes, respectively. A dc voltage was applied to one of the electrodes and the other electrode was grounded. Particles fed to the lower electrode were charged by induction and levitated upward by the Coulomb forces. When the applied voltage was high enough, the particles passed through the mesh electrode. The charge of the particles was measured with a Faraday cup, and the particle behavior was observed with a high-speed microscope camera. The particle charges were also analyzed from experimentally obtained particle trajectories and numerically calculated electric fields. Finally, the conditions for the effective levitation and dispersion of the charged particles and their mechanisms were studied and have been described in detail.