闪电通道垂直假定引起回击辐射场峰值计算误差分析

利用高速摄像系统观测的闪电通道和利用分形方法模拟的闪电通道,分析了通道的垂直假定对回击辐射场峰值计算的影响。结果表明,回击电磁场随方位角的变化非常明显,在距闪电通道几百米距离,误差可达2倍;在1km处,闪电通道的垂直假定对时域回击辐射场峰值计算的相对误差最大为50%左右,平均小于10%。随距离的增加,误差逐渐减小。

Analysis of Calculated Return-Stroke Radiation Field Peak Errors Induced by Vertical-Path Assumption

Using the lightning path taken by the high speed camera and the simulated lightning path, the electric field peak errors are analyzed by assuming the lightning path being vertical. The results show that at close distances, the field waveform is dependent strongly on azimuth; at distance of several hundreds, the ratio of the peak error values at two azimuths may be bigger than 2; at the distance of 1 km, the mean error is less than 10% with a maximum value of 50%.The calculated relative error decreases with the increasing of distance.