Research On Simulation Of Lightning Protection Design For Aircraft Radome

Aircraft radome aims to protect the radar antenna from the external environment.However,the radome is vulnerable to breaking,lancinating and even exploding caused by lightning strike when the plane is in the air,which threats to flight safty.So it is very important to study the lightning protection for aircraft radome.Due to the high cost of lightning test,based on a 3D electromagnetic field simulation software,three parts,including the radome materials and structure impacting on electric field distribution,the breakdown characteristic of lightning protection device,the layout of lightning protection device,are studied to explore related issues of radomes lightning protection in this paper.Firstly,research situation of radome lightning protection at home and abroad are described.Then,the lightning theory,lightning strike to airplanes and the mechanism of lightning strike to radomes are described to elaborate the connect between lightning and radomes,which lay a foundation for the emulation analysis.Secondly,the effect of the material and structure of the radome on lightning protection is studied.Based on a highly non-uniform electric field generated by the rod-plate electrode,the relative permittivity and thickness of dielectric radome and the resonant cell style of metamaterial radome are studied to explore how they affect the electric field distribution inside and outside the radome.The results show that the change of relative permittivity of the radome within 50 makes a great influence on the electric field near the antenna,and the resonator style makes little effect on the electric field distribution.Thirdly,the effect of strips' breakdown characteristic on lightning protection is studied.Based on actual size of segmented strips,the mathematical model is developed,and the gap breakdown electric field is formed by setting the potential difference between the first and the last button.Four parameters,including the button gap,the button shape,the button size,and relative permittivity of the strip,are studied to explore how they affect the breakdown characteristic of lightning diverter strips.The results show that the breakdown characteristic of lightning diverter strips can be improved by narrowing the button gap,decreasing the base-band relative permittivity and using the oval button.Finally,the influence of strips' layout on lightning protection for the radome is studied.Based on the antenna corona criterion proposed by A.Delannoy,in a highly non-uniform electric field,the change in the length and number of solid and segmented strips is studied to explore how they affect the electric field near the antenna.The results show that the range of strips length with high lightning protection efficiency is obtained.With the increasing number of strips,the antenna farther away from the wall,the lightning protection effect of segmented strips is more similar to the solid strips.