弯曲雷电回击通道的建模及其辐射场计算

Formulation the Model of a Kind of Tortuous Lightning Channel and Calculation of Its Radiated Fields

在对雷电回击过程产生的电磁辐射场进行计算时,大部分文献都假设云地放电通道是一条直线,但直线雷电回击通道模型不能准确反映雷电回击通道的物理特性。本文对雷电弯曲回击通道进行了建模,并提出了回击通道辐射电磁场有效观察距离的概念。本模型可以精确刻画雷电辐射电磁场波形的次峰和振荡等特点,模拟其高频频谱分量。研究了弯曲通道的电流线段倾斜角度、雷电流回击速度、观察距离对其辐射电磁场的影响。

When calculating the radiated fields generated from lightning stroke return,major literatures assume that cloud-to-ground path is a straight line.But straight-line model does not reflect the physical features of lightning return stroke channel exactly.In this paper,the model of a tortuous lightning channel is formulated,and the concept of effective observable distance of lightning return stroke channel's radiated field is proposed.This model can precisely describe the sub-peaks and oscillation of radiated fields,and model the high frequency spectrum.In addition,this paper also discusses the effects that current segment's tilt angle,current propagating velocity and observable distance have on radiated fields.