雷电流波形的观测及沿通道时空分布的数值模拟

Observation and Numerical Simulation of Lightning Discharge Current Along the Lightning Channel

2005年夏季在山东利用人工引发雷电技术,在放电通道底部测量到了微秒量级的10次回击电流波形.基于Diendorfer and Uman(DU)模式,本文对雷电回击电流波形沿通道的时空分布特征进行了数值模拟.结果表明,如果合理的选取参数,基于DU模式的模拟结果与光学观测结果基本一致;与其他模式相比,DU模式是更合理的.

Artificially triggered lightning experiment was conducted in Shandong Province in the summer of 2005,10 return strokes current waveforms in microsecond time resolution have been obtained in the channel bottom. Based on the Diendorfer and U- man（DU） model, the current waveforms characteristics along the channel are simulated and discussed. It is found that the simulated current waveforms along the lightning channel are in agreement with the optical measurements when the two different discharge time constants are properly chosen; compared with other return stroke models, the DU model is more physically reasonable and more preferable.