前人已将基于天线理论建立的闪电回击模型(AT)就回击过程的远区电磁场计算结果与其他回击模型,如传输线模型等及实验数据进行了详细的对比验证,得到较为吻合的结果.但针对闪电通道附近磁场并未进行实验验证,为验证AT模型在该距离上磁场计算的有效性,2015年在山东滨州中国科学院大气物理研究所的野外人工触发闪电实验基地设计并实施了相关实验,为了数据的可靠,在距离闪电通道55 m和78 m两点分别设置了磁天线采集闪电回击磁场.基于2015年夏天的一次成功人工触发闪电实验中采集的距离闪电通道55 m和78 m的磁场数据,与基于cSr Studio建立的AT模型的仿真磁场(55 m和78 m)在时域和频域上对比,都得到较好的吻合结果,从而说明在AT模型在闪电通道近区针对回击过程磁场环境的仿真计算是可靠的.
The electromagnetic far field of return stroke calculated by using the antenna-theory model (AT) has been verified compared with another return stroke models, such as transmission line model.The results matched well.However, the validity of using the AT model to calculate the magnetic fields close to lightning channel has not been verified.To verify the effectiveness of AT model and calculate the magnetic field at such distance, we have designed and done experiments at Shandong Artificially Triggering Lightning base of Institute of Atmospheric Physics.To improve the reliability of data, we placed two magnetic field sensors at 55 m and 78 rn away from the channel to collect the magnetic field.In this paper, the magnetic fields produced by the return stroke current in classical rocket-triggered lightning as measured at 55 m and 78 m distance during the Shandong Artificially Triggering Lightning Experiment (SHATLE) in 2015 summer were compared with the magnetic fields calculated by the AT model at 55m and 78m.The simulation results both on time-domain and frequency-domain are generally in consistent with the measurements at 55m and 78m which mean that using the AT model to simulate and calculate the magnetic field of return stroke nearby is reliable.