Simulation of a Positive Corona Discharge from a Plane-Parallel System of Horizontal Grounded Wires in the Electric Field of a Thundercloud

Abstract: We study theoretically a non-stationary positive corona developing in free space from a system of grounded wires suspended at the same height and placed in a uniform thundercloud electric field growing with time. To calculate the corona characteristics, a two-dimensional computer model has been developed. The discharge is described by an equation for the density of positive ions of a single species and Poisson’s equation for the electric field. It is assumed for simplicity that the wires are identical and the neighboring wires are separated by the same distance. The two-dimensional calculations are performed for the system composed of infinite number of parallel wires, when the problem is reduced to studying the corona from one wire, and for the system consisting of eight parallel wires. The corona current, the distribution of the space charge generated by the corona, and the electric field about the wires are found. In the case of the corona from the infinite number of the wires, the calculated corona current reaches saturation and depends only on the growth rate of the thundercloud electric field and the distance between the wires. The results may be of interest for subsequent assessments of the reliability of multi-wire lightning protection.