Q6儿童假人腹部腰椎有限元模型的建立及验证

发布时间：2018-01-17 17:20

本文关键词：Q6儿童假人腹部腰椎有限元模型的建立及验证　出处：《湖南大学》2016年硕士论文　论文类型：学位论文

【摘要】：汽车碰撞儿童假人是用于研究碰撞过程中儿童损伤机理及评估汽车对儿童保护能力的重要工具。2013年欧洲经济委员会(ECE)开始对儿童安全法规进行修改,Q系列儿童假人在新的法规中被提出用以替换以往使用的P系列儿童假人。然而目前并没有公开的Q6儿童假人有限元模型可用于汽车碰撞有限元仿真,因此现阶段研究Q6儿童假人各重要部件的有限元建模方法有着重要意义。本文首先介绍了现有儿童假人的类型、开发儿童假人的常用方法以及Q6儿童假人的结构特点和主要参数。针对Q6儿童假人的不同部位采用直接建模法和基于逆向工程的三维激光扫描法以及CT扫描法,建立了精确的Q6儿童假人几何模型,并利用新型排水法和方程法对Q6儿童假人关键部位的材料密度进行反求。在建立的Q6儿童假人几何模型的基础上,对其腹部和腰椎进行了细致的网格划分,并参照现有儿童假人有限元模型选取合理的材料模型和材料参数初值。为了获得准确的腹部材料参数,本文采用结合有限元仿真和设计试验通过优化手段反求材料参数的方法。对假人腹部进行压缩试验获得优化目标曲线,同时建立模拟腹部压缩试验的有限元仿真模型,通过LS-OPT软件对各材料参数的灵敏度分析确定优化变量,采用基于纵坐标的曲线匹配法和混合遗传算法最终得到反求后的材料参数值。最后建立了模拟Q6儿童假人腹部标定试验的仿真模型,仿真结果表明该有限元模型满足标定要求,验证了所建立Q6儿童假人腹部有限元模型的有效性。对于Q6儿童假人腰椎有限元模型,建立了模拟腰椎正向标定试验的仿真模型,对比已知试验曲线,初步验证了腰椎所选取材料模型和材料参数初值的可靠性。通过同样的材料参数反求方法,对腰椎关键材料参数进行优化,最终优化后的腰椎有限元模型完全满足标定要求,从而验证所建立Q6儿童假人腰椎有限元模型的有效性。
[Abstract]:Car crash child dummy is an important tool for studying the mechanism of child injury and evaluating the ability of automobile to protect children during collision. Economic Commission for Europe (ECEE) 2013. Amendments to child safety regulations have been initiated. Q series child dummy is proposed in the new regulations to replace the P series children dummy used in the past. However, there is no open Q6 child dummy finite element model which can be used in vehicle crash finite element simulation. Therefore, it is of great significance to study the finite element modeling method of the important parts of Q6 child dummy at this stage. Firstly, this paper introduces the existing types of children dummy. The common methods of developing child dummy and the structure characteristics and main parameters of Q6 child dummy were developed. Direct modeling method, 3D laser scanning method based on reverse engineering and CT scan were used for different parts of Q6 child dummy. Drawing. A precise geometric model of Q6 child dummy was established, and the material density of the key parts of Q6 child dummy was inversely calculated by using new drainage method and equation method, based on the established geometric model of Q6 child dummy. The abdomen and lumbar vertebrae were divided carefully, and the reasonable material model and the initial value of material parameters were selected according to the existing finite element model of children dummy, in order to obtain accurate abdominal material parameters. In this paper, the optimal target curve is obtained by compression test on the abdomen of dummy by using the method of optimizing material parameters by combining finite element simulation and design experiment. At the same time, the finite element simulation model is established to simulate abdominal compression test, and the optimization variables are determined by the sensitivity analysis of each material parameter by LS-OPT software. The curve matching method based on the ordinate and the hybrid genetic algorithm were used to get the material parameter value. Finally, the simulation model was established to simulate the abdominal calibration test of Q6 child dummy. The simulation results show that the finite element model meets the calibration requirements and verifies the effectiveness of the established finite element model of Q6 child dummy abdomen. The simulation model of simulating lumbar vertebrae forward calibration test is established, and the reliability of the selected material model and the initial value of material parameter is preliminarily verified by comparing the known experimental curves. The key material parameters of lumbar vertebrae were optimized, and the optimized finite element model of lumbar vertebrae fully met the calibration requirements, thus validating the validity of the Q6 child dummy lumbar spine finite element model.
【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

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