某机翼疲劳寿命估算

FATIGUE LIFE PREDICTION OF AN AIRCRAFT WING

对整个机翼进行了有限元分析,危险孔周围的细节分析使用精确的三维元,计算中考虑了复杂载荷历程,选取了几个飞行姿态。机翼危险部位寿命估算结果与疲劳试验一致。

Finite Element Analyses are carried out for a complex aircraft wing structure and more detailed analyses are made by using refined three-dimensional mesh at the critical hole region.Several aircraft flight attitudes to account for the complicated load histories are analyzed. Neuber's formula is used to convert elastic stresses at critical point from FEM into elastoplastic stresses and strains. Different cyclic stress-strain curves of the relevant material are considered and results compared. The fatigue damage is accumulated cycle by cylcle and the structure life is reached when the damage reaches unity.The predicted life of the aircraft wing agrees well with the actual fatigue test.