机车车辆端部结构拓扑-参数一体化优化方法

拓扑优化方法广泛用于获取结构的优化构型,而参数优化方法用于具体结构参数的取优,为了整合这两种方法的优势并提供一体化优化方案,以机车车辆端部结构被动安全性为研究对象,提出一套可以同时考虑静态和动态载荷作用,适用于大尺寸结构的拓扑-参数优化方法。该方法的拓扑优化部分采用缩放能量权重的混合元胞自动机方法对端部结构进行综合耐撞性和刚度评估的拓扑优化设计,有效解决拓扑优化多工况中由于能量差异而导致的结果偏差;参数优化部分结合网格变形技术和自适应模拟退火优化算法对结构进行给定接触力约束条件下的参数优化。具体算例结果表明,利用该方法优化后机车车辆在正面碰撞中的关键接触力峰值下降26.2%~46.3%,变形模式更趋于合理;在侧翻碰撞中乘客生存区间的上下部安全距离分别增加24.8%和12.8%。

Holistic Topology-parameter Optimization Method for the Rail Vehicle End Structure

The topology optimization method is widely used to obtain the optimized geometry shape of a structure; the parameter optimization method is generally used to determine the optimal value of a parameter. In order to integrate the advantages of two methods, a holistic topology-parameter optimization method for the end structure of vehicles is proposed, which can consider both static and dynamic loads and is meanwhile suitable for large-scale structures. The scaled energy weighting based Hybrid Cellular Automata(HCA) method is used to perform the topology optimization for comprehensive crashworthiness and stiffness assessments of end structure, which can effectively solve the result deviation caused by the energy difference in multi-working conditions; the grid deformation technology and the adaptive simulated annealing optimization algorithm are combined to optimize the parameters of the structure under the given contact force constraints. With the application of this method to the optimization of end structure of a vehicle, the critical peak contact force drops by 26.2%-46.3% in the frontal collision, meanwhile the deformation is more reasonable; the upper and lower safety distance of the passenger living space increases by 24.8% and 12.8% in the rollover collision, respectively.