The Effect of Dielectrophoresis on the Flow of Granular Materials

Electrostatic charging can affect granular materials in a number of ways, and while electrostatics has been utilized by several industries, it can lead to significant flow problems for many other industries. Electrostatic effects can be especially problematic in the pharmaceutical industry, where it is necessary to control precise mixtures of granular material and distribute them evenly. Unpredictable electrostatic phenomena can cause agglomeration and segregation of granular material that should be evenly distributed. We investigate how dielectrophoresis (DEP), caused by non-uniform electric fields affect different granular materials. Using a Van de Graaff generator and a grounded metal rod, we studied how granular materials adhered to the rod in a non-uniform electric field, and how varying the voltage, humidity, particle size, grain size, grain coatings, and grain conductivity influenced the amount of adhesion. Additionally, we investigated how non-uniform electric fields affected the flow of granular materials from a hopper.