Study on the Effectiveness of Single Lightning Rods by a Fractal Approach

Abstract

Lightning rod is widely used in lightning protection systems. It is of practical interest to analyze the protective performance of a lightning rod taking into consideration some stochastic behaviors of the lightning process. The effectiveness of a single lightning rod is investigated in this paper using a fractal growth approach based on dielectric breakdwon model (DBM). The effective interception area, the strike distribution on rod and the protection zone of single lightning rods of various heights are calculated. Comparing our results with those of the rolling sphere method, it is shown that, the fractal approach is able to make reasonable evaluation of the lightning protective performance. New features such as the inherent vulnerability of the rod to lateral strikes and the division of the protection zone into three regions are also presented.