基于大客车碰撞分析的新型 PVC 护栏梁板拓扑优化

摘要

In order to develop a new barrier to adapt to the trend of “plastics to replace steel”,according to domestic current available evaluation standards,the crashworthiness topological optimization analysis was implemented for a PVC barrier through establishing a FE model of a system of “vehicle-barrier”and combining the topological optimization method of a cellular automaton.Firstly,the key factor to enhance the barrier beam's bending stiffness was obtained with the comparison between material mechanical properties of Q235 and PVC based on the barrier beam design theory. Secondly,the beam topological configuration was acquired with several crashworthiness topological optimization analyses under different operation conditions. Finally, the crashworthiness verification analysis for the new barrier beam configuration of “guasi-H”type was performed using the simulation software.The analysis results indicated that the barrier beam topological configuration with 0.25 mass fraction can realize the protective capability of A level for a 10 t passenger car;the maximum lateral displacement of the barrier beam is 785 mm;the vehicle's maximum acceleration in X,Y,Z directions are 6.67g,4.93g and 2.16g to meet the requirements of the impact safety standards.%为了开发出一套新型“以塑代钢”PVC 护栏，根据国内现有的评价标准，通过建立汽车－护栏有限元模型，并结合元胞自动机的拓扑优化方法，展开了对客车碰撞条件下的新型 PVC 护栏梁板截面耐撞性拓扑优化分析。首先，根据护栏梁板设计理论，在对比 Q235与 PVC 材料力学性能中，得出了增大梁板弯曲刚度的重要因素；其次，利用耐撞性拓扑优化方法，对梁板设计域进行了不同工况下的拓扑优化分析，并得出了 PVC 护栏梁板拓扑构型；最后，利用仿真软件针对所提取的近“H”型梁板拓扑构型进行了仿真验证分析。分析结果表明：0．25质量分数下的梁板拓扑构型能够对10 t 客车实现 A 级防护能力，护栏梁板的最大横向偏移量为785 mm，车体 X、Y、Z 轴的最大加速度分别为6．67 g、4．93 g、2．16 g，均小于评定标准的20 g，满足碰撞安全性标准要求。