On Lightning Electromagnetic Field Propagation Along an Irregular Terrain
On Lightning Electromagnetic Field Propagation Along an Irregular Terrain
复制标题
雷电电磁场沿不规则地形的传播
DOI：
10.1109/temc.2015.2483018
复制
发表时间：
2016-02-01
影响因子：
2.1
通讯作者：
Wang, Zhenhui
中科院分区：
文献类型：
--
作者：
Li, Dongshuai;Azadifar, Mohammad;Wang, Zhenhui
在本文中，我们提出了一个理论分析的雷电电磁场的传播效应在山区地形。支持的分析是由实验观测组成的同步记录的雷电流和电场与向上的负闪电在瑞士的仪器化的Saujntis塔。雷电电磁场沿着山周围的区域传播的Sa ntis塔使用全波的方法，基于时域有限差分法，并使用二维地形图沿着塔和现场测量站之间的直接路径位于约15公里的塔。我们表明，考虑到真实的不规则地形之间的Sa ntis塔和现场测量站，无论是波形和振幅的模拟电场与回击和快速初始连续电流脉冲是在很好的协议与实测波形。另一方面，平坦地面的假设导致对峰值电场的显著低估。最后，我们讨论了所获得的结果的灵敏度的假设值的回程速度和地面电导率，所采用的回程模型，以及存在的传感器所在的建筑物。
In this paper, we present a theoretical analysis of the propagation effects of lightning electromagnetic fields over a mountainous terrain. The analysis is supported by experimental observations consisting of simultaneous records of lightning currents and electric fields associated with upward negative lightning flashes to the instrumented Säntis tower in Switzerland. The propagation of lightning electromagnetic fields along the mountainous region around the Säntis tower is simulated using a full-wave approach based on the finite-difference time-domain method and using the two-dimensional topographic map along the direct path between the tower and the field measurement station located at about 15 km from the tower. We show that, considering the real irregular terrain between the Säntis tower and the field measurement station, both the waveshape and amplitude of the simulated electric fields associated with return strokes and fast initial continuous current pulses are in excellent agreement with the measured waveforms. On the other hand, the assumption of a flat ground results in a significant underestimation of the peak electric field. Finally, we discuss the sensitivity of the obtained results to the assumed values for the return stroke speed and the ground conductivity, the adopted return stroke model, as well as the presence of the building on which the sensors were located.