动载作用下柔性车体结构疲劳寿命的仿真

为准确预测随机动载作用下柔性车体结构的疲劳寿命，将多体动力学仿真和有限元分析相结合，建立了车体多体动力学模型．计算了35个关键部位的载荷历程，并用准静态应力分析法获得了对应的应力影响因子．用模态分析技术获得了车体结构固有频率和模态振型，用子结构技术获得了车体有限元缩减模型．根据危险应力分布、应力时间历程以及Palmgren-Miner损伤理论，利用疲劳分析软件FE-FATIGUE的基于应力的安全强度因子分析法和MATLAB的WAFO技术对柔性车体结构疲劳寿命仿真．仿真结果包括损伤和疲劳寿命预测．

Fatigue Life Simulation of Flexible Carbody under Dynamic Loading

To accurately evaluate the fatigue lives of flexible carbodies under dynamic loading, a full locomotive multi-body dynamic model was established by integrating multi-body dynamic simulation (MBS)and finite element method (FEM). Loading histories at 35 critical positions were calculated, and quasi-static stress analysis method was used to obtain the stresses influence coefficient ( SIC) corresponding to the 35 loading histories. The natural frequencies and modes of vibrations were determined by Modal analysis, and the reduced model of the carbody was derived with substructure technology. Fatigue simulation was finally done based on stress distribution, stress-time histories, and Palmgren-Miner damage theory. In the simulation, the safety factor technology in die software FE-FATIGUE and the wave analysis for fatigue and oceanography (WAFO) tool in MATLA were utilized. Simulation results include predictions on damages and fatigue life.