车辆吸能部件耐撞性的拓扑优化研究

发布时间：2018-04-08 16:04

本文选题：静态拓扑优化　切入点：动态拓扑优化　出处：《湖南大学》2016年硕士论文

【摘要】：随着汽车工业的发展,节能、安全、环保日益成为人们关注的焦点。汽车正面碰撞的安全性是汽车被动安全中十分重要的一环,在汽车发生正面碰撞时,车辆前部吸能部件是主要的承载和传力结构,而吸能部件的吸能特性直接关系到驾驶舱的完整性及传递到乘员的碰撞力和加速度,因此研究正碰工况下的车辆吸能部件的耐撞性具有非常重要的意义。本文基于拓扑优化方法,主要开展车辆正面碰撞工况下前部吸能结构的耐撞性拓扑优化研究,针对福特Explorer车型的分析,对其主要的吸能部件前纵梁和保险杠进行了拓扑优化和尺寸优化,并将验证后的优化结果在整车当中进行了应用。本文的主要研究内容和工作如下:1、在对大量实际车型吸能梁结构尺寸进行测量的基础上,分别研究了不同初始截面、不同初始长度、不同初始材料直梁的动态拓扑优化,得出各种条件下直梁的最佳截面形状和诱导结构的大体位置,为以后汽车直梁件的设计提供了参考。2、针对福特Explorer各部件吸能情况,选取汽车前纵梁前段和保险杠进行耐撞性拓扑优化研究。本文创新性地结合了静态和动态两种拓扑优化方法对汽车前纵梁进行结构耐撞性拓扑优化,综合考虑前纵梁的轴向刚度、侧向刚度和吸能特性,最终确定前纵梁的最佳截面形式与诱导结构的尺寸和位置;针对保险杠进行动态拓扑优化得到保险杠的最佳结构形式。对优化后的前纵梁和保险杠进行重构并进行尺寸优化,得出铝合金前纵梁和保险杠各部分的具体厚度尺寸。3、对优化前后的汽车前纵梁和保险杠进行吸能特性仿真对比分析,结果表明,优化后铝合金前纵梁的比吸能是原来钢质前纵梁比吸能的3.7倍,最大碰撞力减少了32.77%,单根前纵梁的质量减少了2.59kg;优化后铝合金保险杠的比吸能是原来钢质保险杠比吸能的3.2倍,且质量降低了2.51kg,符合轻量化要求;把得到的前纵梁前段和保险杠的优化结果应用到福特Explorer上,对整车进行正面100%重叠率刚性壁碰撞仿真分析,结果表明,整车的耐撞性能得到了一定的改善。
[Abstract]:With the development of automobile industry, energy-saving, safety and environmental protection have become the focus of attention.The safety of vehicle frontal collision is a very important part in the passive safety of automobile. In the frontal impact, the front part of the vehicle is the main bearing and transmitting structure.The energy absorption characteristics of the energy-absorbing components are directly related to the integrity of the cockpit and the impact force and acceleration transmitted to the occupants, so it is of great significance to study the crashworthiness of the energy-absorbing parts of the vehicle under the positive impact conditions.Based on the topology optimization method, this paper mainly studies the topology optimization of the front energy absorption structure under the frontal impact condition, and analyzes the Ford Explorer model.Topology optimization and dimension optimization of the front longitudinal beam and bumper of its main energy absorption components are carried out, and the verified optimization results are applied in the whole vehicle.The main contents and work of this paper are as follows: 1. On the basis of measuring the structural dimensions of a large number of practical energy absorption beams, the dynamic topology optimization of different initial cross-sections, different initial lengths, and different initial material straight beams are studied respectively.The optimum section shape of straight beam and the general position of induced structure under various conditions are obtained, which provides a reference for the design of automobile straight beam in the future. Aiming at the energy absorption of each component of Ford Explorer,The front section of front longitudinal beam and bumper are selected to optimize the crashworthiness topology.In this paper, the static and dynamic topology optimization methods are innovatively combined to optimize the crashworthiness topology of the front longitudinal beam. The axial stiffness, lateral stiffness and energy absorption characteristics of the front longitudinal beam are considered synthetically.Finally, the optimum section form of the front longitudinal beam and the size and position of the induced structure are determined, and the optimum structure form of the bumper is obtained by dynamic topology optimization for the bumper.The optimized front longitudinal beam and bumper are reconstructed and the dimensions are optimized. The specific thickness dimensions of each part of aluminum alloy front longitudinal beam and bumper are obtained. The energy absorption characteristics of the front longitudinal beam and bumper before and after optimization are compared and analyzed by simulation.The results show that the specific energy absorption of the aluminum alloy front longitudinal beam after optimization is 3.7 times that of the original steel front longitudinal beam.The maximum impact force decreases 32.77 kg, the mass of single front longitudinal beam decreases 2.59 kg, the specific energy absorption of the optimized aluminum alloy bumper is 3.2 times that of the original steel bumper, and the mass is reduced 2.51 kg, which meets the requirement of lightweight.The optimized results of front longitudinal beam and bumper are applied to Ford Explorer, and the 100% overlap rate rigid wall collision simulation analysis is carried out. The results show that the crashworthiness of the whole vehicle is improved to a certain extent.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U467.14

【相似文献】