Analysis and Comparison of Lightning Return Stroke Models at Altitude

摘要

This thesis presents a comprehensive analysis and comparison of lightning return stroke models. A brief description of the lightning process and deviations of the equations for calculating the electric and magnetic fields at points on the ground and at points at altitude for an arbitrary current waveform are also presented. The models analyzed are the Bruce-Golde model, Uman's transmission line model (the breakdown pulse current not attenuated), and Uman's model using an attenuating breakdown pulse current. Plots of the electric and magnetic fields that these three model predict for various distances and altitudes and different parameters (rise and fall time of the current) are included. The above three models along with a recently modified version of Lin's model (where the breakdown pulse is attenuated) are then compared with recently acquired lightning return stroke electromagnetic data. The data was obtained simultaneously on the ground and at various altitudes in a WC-130 aircraft in South Florida.