Study On Lightning Current And Electromagnetic Field Of High Buildings Under Lightning Stroke

With the improvement of the urban environment,there are more and more high-rise buildings.However,these buildings are more vulnerable to lightning.When a lightning strikes a high-rise building,the strong lightning current flowing through the lightning protection system,produces impulse magnetic field inside the building space,which may disturb the operation of electronic equipment and information system,and may even threaten personal safety.Therefore,it is very necessary to analyze the lightning electromagnetic field.According to the problem of electromagnetic interference in high-rise buildings under the condition of lightning strike,a complex asymmetrical high-rise building model is established.the finite element method(FEM)is used to analyze current distribution and the inner magnetic field distribution of the building,The main research contents are summarized as follows:Firstly,the fundamental theory of the electromagnetic field based on the finite element method(FEM)of COMSOL Multiphysics software is described.Then the lightning current source is analyzed and determined.Secondly,the simplified model of building lightning protection system is established by COMSOL Multiphysics software,the current distribution was obtained in the steel conductor.Compared with the experimental results of the existing literature,the feasibility of the finite element method is verified.In addition,the current distribution of two different simplified models is analyzed.Thirdly,the complex high-rise building lightning protection system is established by COMSOL Multiphysics software,calculating the lightning current distribution on thelightning protection system under lightning conditions,and then considering the effect of different factors on the lightning current distribution.Finally,based on the simulation results above,the influence of lightning strikes on the high-rise building is analyzed through magnetic field contours and the change of the magnetic flux density in the high-rise building,and analyzes the magnetic field distribution in the different lightning strike point,and analyzes the distribution of electric field and in the high-rise building.