Particle movement mode effect on electrostatics

Abstract

In this work, particle electrostatics was studied by experiment methods. A single particle was tested for charge generation through moving along a metal inclined plate. It is found that particle movement mode does an important role in determining electrostatics generation. The sequence of particle movement mode to generate electrostatic charge from high to low is sliding, sliding-rolling and rolling. Particle sphericity determines the mode of particle movement along the inclined plate. The electrostatics generated decreases with increasing sphericity. Such trend becomes less from sliding to rolling and decreases with increasing the plate inclination. The electrostatics generated decreases with increasing the inclined angle of the plate, which causes particles more rolling and less sliding. The effect of inclined angle of the plate on the electrostatic charge generation is more significant for a particle with low sphericity than that for a particle with high sphericity. In addition, a granular pneumatic conveying system was set up to measure the electrostatics generated by multiple particles, where particle movement mode is found to make an obvious effect on electrostatic charge generation. Due to particle–wall contact area being large, sliding particles can generate more electrostatic charge than rolling particles do. It is found that electrostatics increases with particle size, particle loading and pipe length.