基于损伤容限优化的机身开口结构研究

STUDY OF FUSELAGE OPENING STRUCTURE BASED ON DAMAGE TOLERANCE OPTIMIZATION

将飞机结构设计的尽可能理想,如重量轻、强度高、耐久性好等,一直是飞机结构设计师的愿望。应用子模型分析技术,从全局模型中提取感兴趣部位进行细节分析,然后加入损伤容限约束条件,对结构细节进行多目标优化设计。讨论了机身开口结构几何参数对结构寿命的影响,结果显示加强结构附近剩余强度可能发生不减反增的现象,裂纹扩展寿命对开口倒角半径并不很敏感,增加带板厚度在一定范围内能够提高结构寿命。该文方法具有较好的精度和准确性,同时为开口结构设计、优化和检修提供参考及指导。

It has been the desire of aircraft designers that the structures were devised as ideal as possible, such as lighter weight, higher strength and better durability. The sub-model analysis technology is applied to extract the region of interest from global model for detail analysis. Introducing the damage tolerance constraint conditions, muti-objective optimization for the detail design is completed. The relationships between structure life and geometrical parameters of fuselage opening are discussed. The results reveal that residual strength near the reinforcement structure may rise rather than decrease; crack life is not sensitive to fillet radius of opening; increasing the thickness of skin in a certain range can improve structure life. The solutions of proposed method have better accuracy, which provides reference and guidance for the designing, optimization and maintenance of opening structures.