Research On Crack-tip Stress Field And Patching Of The Integral Wing Panel

Abstract:Integral panel structure is an important structure in the modern advanced aircraft, which is mainly applied to fuselage and wing. Integral panel, with good rigidity, tensional strength, fatigue resistance, dynamic performance, has greatly reduced the assembly cycle and manufacturing costs. Due to lacking of rivet hole and crack arrest structure, the damage tolerance of integral panel is insufficient. Therefore, the study on anti-fracture ability in containing crack integral panel is important to the damage tolerance of integral structure.In this paper, integral wing panel is the research object. With the finite element method, the paper researched the crack-tip stress field and crack patching of the integral wing panel on the condition of bending load. The primary investigation contents of this paper mainly included the following five parts:Firstly, the paper introduced the research background, topic originates and research status at home and abroad, and proposed the research contents and methods.Secondly, the paper analyzed the structural features and load of the integral wing panel, constructed the finite element model of containing crack panel and integral wing panel based on the ABAQUS-FRANC3D joint simulation method. Compared with the calculation results between joint simulation method and Newman-Raju formula, and verified the reliability of the joint simulation method.Thirdly, the paper studied the effect of T-beam structure parameters on its carrying capacity with the mathematic derivation method. Based on the joint simulation, it construed the finite element model of the integral wing panel on the condition of bending load, and summarized the effect law of integral panel structure parameters on its crack-tip stress intensity factors,and discussed the optimized structural parameter range.Fourthly, the paper summarized the effect law of patching position, patch shape and patch size on the crack-tip stress intensity factors of the integral panel with the patching integral panel initiate element model,and proposed the confirm rules of the best patch shape and patch size. Finally, the paper researched the patching of containing crack aluminum alloy components through the experiments, made sure of the reliability of the analysis model and research conclusions with comparing the results between experiments and simulations, and the error was analyzed.