Modeling of Electrostatic Charging of Particles in a Shaker

Multiple spherical particles made of polymer are loaded in a metal container, and shaken for a time. Due to impacts on the metal wall, particles develop electrostatic charge. The development of the charge generation was recorded experimentally in our previous work. In this paper we try to develop a physical model on this. A feature in the experiment was that the saturated amount of charge per particle decreased with an increase of the number of particles loaded in the container. This was understood as space charge effect, by which a particle in contact with a wall is affected on its charge transfer due to the external electric field from other charged particles, or charged cloud. How to involve the space charge effect into the charging model will be discussed in details.