高建筑物对矮建筑物保护作用的三维数值模拟  

Three-dimensional Numerical Simulation of the Protective Effect of Tall Building on Short Building

作　　者：吴萌 谭涌波[1] 林雨荷 王雪雯 Wu Meng;Tan Yongbo;Lin Yuhe;Wang Xuewen(Emergency Management College,Nanjing University of Information Science and Technology,Nanjing 210044;State Key Laboratory of Severe Weather&CMA Key Laboratory of Lightning,Chinese Academy of Meteorological Sciences,Beijing 100081)

机构地区：[1]南京信息工程大学应急管理学院,南京210044 [2]中国气象科学研究院灾害天气国家重点实验室/中国气象局雷电重点开放实验室,北京100081

出　　处：《应用气象学报》2023年第6期749-758,共10页Journal of Applied Meteorological Science

基　　金：灾害天气国家重点实验室开放课题(2023LASW-A03);国家自然科学基金面上项目(42275075)。

摘　　要：运用三维高分辨率随机多先导连接模型,设置高矮两座建筑物并改变其中矮建筑物的高度以及高矮两座建筑物水平距离,同时设置孤立矮建筑物进行对照,探究多先导模式下高建筑物对矮建筑物的保护作用。结果表明:高矮建筑物距离较近时,下行先导的发展完全受高建筑影响;随着建筑物水平距离增加,高建筑物对先导主通道仍然存在明显吸引效应。当矮建筑物雷击概率的增长趋势出现明显减缓的分界点,此时与孤立矮建筑物的雷击概率仅相差3.6%,但单次闪电的连接过程仍存在显著差异。通过对比不同建筑物水平距离与孤立建筑物的雷击结果,高矮建筑物水平距离由400 m增至600 m,差异则从44.5%降低至22.7%。在相同高建筑物影响下,不同高度矮建筑物的雷击概率变化趋势亦存在该特征,高度为50,100,150 m和200 m的矮建筑物对应的雷击增长速率分界点的水平距离为300,450,550 m和600 m。Tall buildings distort the electric field of the surrounding environment,resulting in a relatively strong electric field at top corners,which affects the lightning strike process,and the protection effect that short buildings receive from tall buildings varies with the distance between them.A three-dimensional fine-resolution lightning attachment model with multiple upward leaders(LAMM)is used to simulate protection effect of a tall building and a short building with different height and distance,with an isolated building set as a control group.Experimental results show that when there is a tall building with a short building in the space and two buildings are close to each other,the distortion range of the tall building almost completely contains the distortion range of the short building,the development of downward leader is completely affected by the tall building,and the shielding effect of the tall building on the short building is significant.With the increase of the building distance,the shielding effect of the tall building on the short building decreases exponentially.When tall building is 250 m high and the short building is 150 m high,probabilities of lightning strikes on short building with distance from 50 m to 600 m with interval of 50 m are 8.3%,15.0%,26.5%,36.7%,39.5%,47.5%,58.9%,57.0%,56.0%,57.2%,61.0%,and 62.5%.When there is a cut-off point where the increasing trend of the probability of lightning strikes on short buildings appears to slow down significantly,the probability of lightning strikes on short building differs from its probability of lightning strikes in isolation by only 3.6%.Comparing the lightning strike results for different building distance and isolated building,the difference in lightning strike results caused by the presence of tall building decreases from 44.5%to 22.7%when the horizontal distance between tall and short buildings is increased from 400 m to 600 m.Given the height of tall building,the probability of lightning strikes on short building with different heights foll

关 键 词：空间形态 电场畸变 保护作用 数值模拟 多上行先导 

分 类 号：P427.3[天文地球—大气科学及气象学] TU895[建筑科学]