Slightly conducting spheres immersed in a dielectric liquid subjected to a DC field: attraction force, electric field on the liquid and partial discharges

We examine the interaction between slightly conducting solid particles suspended in an insulating liquid and subjected to a DC electric field with reference to the basic physical processes occurring in electrorheological (ER) fluids. These ER fluids are suspensions of small solid particles in an insulating dielectric liquid. The particular rheological properties of ER fluids induced by the application of an electric field on the order of a few kV/mm, arise from the electrostatic forces between particles which tend to gather them into chain- and cluster-like structures and induce in some conditions a gel-like structure