基于多体动力学和有限元法的车体结构疲劳寿命仿真

提出一种多体动力学仿真和有限元法相互结合进行结构疲劳寿命预测的方法,并以机车车体结构为例进行了疲劳寿命计算。利用SIMPACK的多体仿真技术获得车体结构的动载荷历程;在ANSYS中利用准静态应力/应变分析法计算结构危险节点应力影响因子;根据模态分析技术确定车体结构固有频率和模态振型以及危险点位置。最后,基于动应力历程以及Palmigren-Miner损伤理论,利用FE-FATIGUE软件的基于应力的结构安全因子分析法对车体结构进行疲劳寿命预测,其中包括应力应变的循环计数、损伤预测和最终寿命估计。

Carbody Fatigue Life Simulation Based on Multibody Dynamics and FEM

The structure fatigue life prediction method based on the multibody dynamics simulation and Finite Element Method(FEM) is proposed,and the locomotive body structure fatigue life is predicted with this method as an example.The dynamic load histories of the carbody structure are evaluated by applying the SIMPACK multibody system analysis technique;the stress-influencing factors at dangerous nodes are calculated by utilizing the quasi-static stress/strain analysis technology in Software ANSYS;modal analysis is made to determine the inherent frequencies,modal shapes and critical locations of the structure.Finally,on the basis of the stress time histories and Palmgren-Miner theory,the carbody structure fatigue life is estimated by the Software FE-FATIGUE stress-based safety factor technology,which includes stress-strain cycle counting,damage prediction,and finalized life estimation.