Computational estimation of ESD conditions between a charged body and a conductor of floating potential

The paper examines the conditions in which a discharge occurs between a charged body and a floating conductor, in air, at atmospheric pressure. The study, which primarily aimed at simulating a class of hazardous situations quite often met in the operation of electronic circuits, is also of interest to those involved in the research and development of electrostatic technologies for processing of particulate matter: separation of granular mixtures, precipitation of dust, spraying of powders. The boundary element method was employed for the analysis of the electric field in the gap between the charged body and the conductive disk at floating potential, located above a grounded plate. The computations were carried out for bodies of various shapes and sizes; some of them addressed the case of a grounded plate covered with an insulating layer of known permittivity. The data on field distribution represented the input data of another program, which estimated the breakdown conditions of that air-gap. The study enabled the estimation of the energy involved in this type of electrostatic discharge and the prediction of the related hazards.