A four-way coupled CFD-DEM modeling framework for charged particles under electrical field with applications to gas insulated switchgears

Abstract

Particulate flows with charged particles under electric flow field exist in many practical applications, including metal particles in Gas Insulated Switchgear (GIS) or manipulation of powders in fluidized bed. The motions of these particles are affected by the electrical field, ambient flow and collisions. This work further develops the four-way coupled CFD-DEM framework under electric field, which not only computes the coupling of flow field, electric field with particle motion and particle charge, the particle-occupied solid fractions on CFD cell, particle-particle interactions and particle-wall interactions, but also considers the dielectrophoretic force, particle-particle Coulomb force, virtual mass force and Magnus force. Particle electrification on its contact with electrode is computed as well. Besides, the multi-sphere model is also introduced into the present framework in order to simulate particles of irregular shapes. The model is validated with theoretic solutions and experiments, and is applied to GIS and fluidized bed. Based on the framework, statistic information from the particulate flow in GIS, e.g., time-averaged solid fraction, time-averaged electric field or particles' velocity and charge distribution are analyzed. A dimensionless number is proposed to predict the particle motion in GIS with Alternating Current (AC), which is further conducive to reducing the parameter window in relevant simulations and studies.