Optimization Of Composites Lightning Protection Based On Electro-thermal Coupling Model

Composite structure is widely used in the design of modern civil aviation aircraft,but compared with the metal structure,its conductivity is poor,in the lightning environment is vulnerable to lightning,resulting in structural damage,to the flight safety is a serious threat.In this paper,the ablative damage characteristics and protection performance of composite lightning protection system are studied by combining theoretical analysis and numerical calculation.Based on maxwell’s charge conservation equation and energy conservation principle,by introducing the parameters "electric displacement vector" and "heat transfer coefficient of metal",the electric-thermal coupling governing equation and energy balance mathematical model of composite lightning protection are obtained.Respectively on the basis of theoretical analysis,established the total aluminum and local aluminum and copper network protection of composite laminated plate lightning ablation damage 3 d finite element model,using ABAQUS software to carry on the numerical simulation,the calculation results are in good agreement with experimental results of literature,and then analysis parameters such as thickness of protective layer and lightning current ablation of laminated plates,the influence law of damage area and the damage characteristics.Finally,the collaborative optimization model of composite lightning protection was established to optimize the lightning damage area,the quality of the protection layer and the ablation rate of the protection layer.The research results have certain reference value for the selection of maintenance task and the determination and analysis of maintenance interval of domestic civil aircraft L/HIRF.