基于塑性铰理论的车身概念设计正碰分析与优化方法

在概念设计阶段,车身碰撞安全性能评价是一个难点问题,需要详细的结构模型,本文基于塑性铰理论提出采用梁单元简化模型对框架车身进行概念设计阶段的耐撞性评估和优化设计方法。首先,介绍了关于箱型截面薄壁梁弯曲特性研究的理论模型与计算过程,接着赋予梁单元塑性铰的特性,模拟薄壁梁变形,再对框架车身进行了碰撞仿真。将仿真结果与详细模型对比,以分析简化模型的精度及可靠性。最后,以此为基础对框架车身进行耐撞性优化。结果表明,该简化模型易于创建,且有较高的精度,可用于概念设计阶段梁结构的设计工作。

Forward collision analysis and optimization method of body conceptual design based on plastic hinge theory

In the conceptual design stage,the evaluation of vehicle body collision safety performance is a difficult problem,which requires a detailed structural model.Based on the plastic hinge theory,this paper proposes a simplified model of beam elements to evaluate and optimize the crash-resistance of the frame body during the conceptual design stage.Firstly,the theoretical model and calculation process of Kecman''s research on the bending characteristics of thin-walled box-section beams are introduced.Then,the plastic hinges of beam elements are given to simulate the deformation of thin-walled beams,and then the crash simulation of the frame body is carried out.The simulation results are compared with the detailed model to analyze the accuracy and reliability of the simplified model.Finally,the crashworthiness of the frame body is optimized.The results show that the simplified model is easy to create and has high precision,which can be used in the design of beam structures in conceptual design stage.