Examination of the Cooray‐Rubinstein (C‐R) formula for a mixed propagation path by using FDTD
Examination of the Cooray‐Rubinstein (C‐R) formula for a mixed propagation path by using FDTD
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DOI：
10.1029/2011jd017331
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发表时间：
2012-08
影响因子：
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通讯作者：
Qilin Zhang;Dongshuai Li;Y. Fan;Yuanyuan Zhang;J. Gao
中科院分区：
文献类型：
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作者：
Qilin Zhang;Dongshuai Li;Y. Fan;Yuanyuan Zhang;J. Gao
文[1]将Cooray-Rubinstein(C-R)公式推广到混合传播路径(垂直分层电导率)，估算了混合传播路径上闪电的水平电场，并用时域有限差分法(FDTD)检验了该公式在距离闪电通道100m~1000m范围内的精度。当观测点附近的地面电导率小于触发点附近的地面电导率时，值得注意的是，在回击开始后的最初几微秒内，C-R公式能够预测出令人满意的精度。然而，当观测点附近的地面电导率大于触发点附近的电导率时，C-R公式预测的初始负漂移被低估了，并且误差随着两段电导率之差的增大而增大。
[1] In this paper we extend the Cooray-Rubinstein (C-R) formula into a mixed propagation path (vertically stratified conductivity) and estimate the lightning horizontal electric fields over the mixed path, and we have examined its accuracy at distances of 100 m to 1000 m from the lightning channel by using finite difference time domain (FDTD). When the ground conductivity near the observation point is less than that near the strike point, it is noted that the C-R formula predicts a satisfactory accuracy in the initial several microseconds after the beginning of the return stroke. However, when the ground conductivity near the observation point is larger than that near the strike point, the initial negative excursion predicted by the C-R formula is underestimated, and the error increases with the increase of the difference between the two sections conductivity.