Electrostatic discharges from charged cylindrical bodies to grounded or floating surfaces

Most of the studies carried out on the hazards related to electrostatic discharges (ESD) assume that the breakdown strength of air, at atmospheric pressure, is 30 kV/cm. The authors have developed numerical techniques for a more accurate estimation of the conditions in which a self-sustaining discharge can occur between conductive bodies of different shapes and sizes. An analysis is presented of three ESD events involving charged cylindrical bodies in the proximity of grounded or floating surfaces. The voltage at breakdown, the critical charge that triggers the discharge, the charge exchanged between the two bodies, and the energy transferred in the discharge are evaluated as functions of various geometric parameters. The interpretation of the results provide a better understanding of the multitude of factors which determine the probability of a discharge and the relative severity of such an event in various technical systems.