3维电介质击穿模型在雷电防护系统评估试验中的应用  

Application of three-dimensional dielectric breakdown model to lightning protection system evaluation

作　　者：陈强[1] 魏光辉[1] 陈亚洲[1] 万浩江[1] 

机构地区：[1]军械工程学院静电与电磁防护研究所,石家庄050003

出　　处：《强激光与粒子束》2011年第3期721-726,共6页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(51077132)

摘　　要：采用荷电圆盘雷云解析模型作激励源,利用电介质击穿模型进行了地闪先导放电高分辨力3维数值模拟,得到了50 m分辨力的地闪放电图样与先导近地500 m时的地面电场分布(峰值-164.9 kV.m-1),结果与实际观测值相符。模拟中通过高维样条插值实现了计算空间与评估区域的分辨力转换(50 m到1 m),构建评估模型,可以进行雷电防护系统的数值评估试验。用该方案对一种雷电防护系统概念模型进行了试验,结果显示:系统10 m高-、1.5 MV激励的条件下,5 m高处的雷击概率以系统为中心随距离增加而增大,系统投影区域雷击概率为0;由于先导激励地面电场的非对称性,保护区范围各向分布极不均匀。通过此方案可以得到系统作用下精细的雷击概率分布,适用于雷电防护系统效能评估。To develop the evaluation methods of lightning protection system,the high resolution simulation of cloud-to-ground lightning leaders was done based on a 3-D dielectric breakdown model（DBM） in an analytic thunderstorm model,then an evaluation model was established near ground and the evaluation experiment was done.The space resolution is 50 m and the evaluation area resolution is 1 m in the experiment,which could satisfy modeling definition.Using successive overrelaxation method to solve the 3-D DBM,the trace of cloud-to-ground step lightning leaders and potential distribution in space could be gotten.When step lightning leaders arrive at the boundary of evaluation area,2-D cubic spline method is used to transform the resolution between space and evaluation area.When leader tips approach the striking range,the unitary E-field near buildings in the evaluation area and the unitary striking probability could be gotten,and the building struck could be selected by Monte Carlo method.Thus the lightning protection system could be evaluated with statistical data of large quantities of experiments.An example was given to test the evaluation model.

关 键 词：电介质击穿模型 地闪先导 分形生长 评估模型 分辨力转换 

分 类 号：P483[天文地球—大气科学及气象学] P427