Structural Optimization And Reliability Analysis Of Aircraft Engine Pylon

In recent years,with the rapid development of the aviation industry,the dimension of aircraft is constantly expanding,the structure is more complex,the load is getting larger and larger,and the requirements for aircraft performance are also higher.In order to improve economy,the problem of weight reduction of aircraft has become an important research topic.The lightweight design of the structure is a major means of aircraft weight reduction.Experts and scholars at home and abroad have conducted a lot of research and practice in this respect.The aircraft engine pylon structure is an important structure connecting the fuselage and the engine,withstanding the weight of the engine,transmitting the thrust,and isolating the engine fire zone.Therefore,the strength,weight,reliability and safety of the pylon have an important influence on the overall performance of the aircraft.In this paper,an initial model is created based on the box-type beam structure pylon,and the topology-size-shape two-level and three-layer lightweight design is adopted to obtain a new structural form that meets the airworthiness requirements and the performance is improved,mainly including:(1)Design area filling for traditional box beam hanging,and get the initial optimization model,The topology optimization was performed by variable density method(SIMP).The first topology optimization determine the main structure and topological relationship of the suspension,the second topology optimization for areas where material is deposited and stress is small to further remove the excess material.(2)Topology optimization is only a conceptual design.It requires size optimization and shape optimization for detail design,optimizing overall wall thickness size,changing hole shape,reducing maximum stress value,and finally obtains a complete structural optimization model.Compared with the traditional box beam structure pylon,the weight is reduced and the mechanical properties are improved.Monte Carlo reliability analysis of the optimized pylon model is carried out to verify the static strength reliability of the pylon under two dangerous conditions meets the requirements,which proves the rationality of the optimization scheme.