Application of an electrodynamic balance to the study of particle-fluid interactions

Abstract

An electrodynamic balance was used to study the aerodynamics and mass transfer characteristics of spherical and nonspherical particles up to 200 μm in size. The balance uses an electric field established by a DC potential to a pair of end electrodes and an AC potential to the central electrode to suspend single changed particles. The suspended particle is then subjected to a steady and/or oscillating air jet. Results from this study indicate that the drag coefficient of irregular-shaped particles was greater than that for spheres, and was unaffected by rotation. Measured mass transfer rates for irregular-shaped naphthalene particles were consistently higher than values predicted for equivalent spheres. These results suggest a strong influence of mass transfer on particle shape and particle Reynolds number.