基于LS-DYNA的7075铝合金汽车保险杠碰撞仿真分析

为了使汽车轻量化,将7075铝合金应用于汽车保险杠系统中。通过有限元软件LS-DYNA对不同厚度保险杠模型的低速对中碰撞进行仿真分析,选用2.5 mm厚加强板和2.0 mm厚齿状横梁,相比原钢质保险杠质量下降20.5%。最后对所选保险杠进行对中碰撞仿真分析。结果显示该保险杠不仅质轻,而且吸能充分,满足碰撞安全要求。     

货车保险杠低速碰撞性能仿真

在低速碰撞过程中,保险杠发挥了举足轻重的地位.根据保险杠低速碰撞的法规要求,应用显式动力有限元分析软件LS-DYNA,对某型货车的保险杠总成进行了低速碰撞仿真研究.通过对吸能情况、加速度时间历程曲线进行分析研究,对该型保险杠碰撞性能的提高提出了改进建议.     

基于非线性回归分析的保险杠横梁优化设计

通过优化汽车保险杠的横梁结构,提高了汽车的碰撞安全性。用ABAQUS软件应用有限元法对9种不同的设计方案进行仿真计算,然后利用MATLAB对模拟数据进行非线性回归分析。通过拟合方程对钢壁厚度和轮廓半径进行优化,当汽车以时速8.0467km/h(参照IIHS低速碰撞法规)碰撞刚性壁障后,保险杠系统在最大变形和应力限制内单位质量吸能(比吸能)最大,提高保险杠低速碰撞时的耐撞能力。     

基于汽车低速碰撞的前保险杠系统安全性能研究

以某乘用车前保险杠系统为研究对象,首先基于加拿大法规CFVSS215建立了正面碰撞和角度碰撞两种工况的保险杠低速碰撞有限元模型。其次从吸能、碰撞器加速度、碰撞器侵入量、横梁变形量和恢复系数几个方面对仿真结果进行分析,结果表明此保险杠在低速工况下具有较好的吸能作用,能很好地保护后部车体,但是恢复能力一般。最后提出改进方案,改进后的保险杠质量降低了21%,两种工况下的恢复系数分别增加了21.95%和96.88%,极大地提高了保险杠碰后恢复能力,而且还实现了轻量化目标。     

碰撞条件下的保险杠系统轻量化研究

前保险杠系统的轻量化可以减小能源消耗,降低成本,但须满足相关碰撞安全标准.在有限元软件HyperMesh中构建前保险杠系统模型,进行低速正面碰撞仿真验证模型的可靠性.定义变量、确定优化目标和约束条件后,创建Kriging代理模型,验证模型正确性.通过NSGA-II算法对代理模型优化求解,选取最优解,并根据仿真结果对最优...     

基于 LS-DYNA 的复合板保险杠可行性研究

运用 ANSYS/ LS-DYNA 软件对复合板应用于汽车保险杠进行了仿真模拟,根据保险杠低速碰撞试验规范-SAEJ2319,把不同厚度比的 PP/低碳钢复合板保险杠与单层的 PP 保险杠和单层低碳钢保险杠的碰撞性能进行对比,分析所得出的变形,加速度,碰撞应力应变,能量等特征参数后发现复合板的碰撞综合性能较好,其中厚度比为2：1的PP/低碳钢复合板碰撞综合性能最好。为 PP/低碳钢复合板运用于汽车保险杠的可能性提供了参考依据。     

小客车保险杠低速碰撞仿真研究

在低速碰撞过程中，保险杠发挥了举足轻重的地位，根据保险杠低速碰撞的法规要求，应用显式动力有限元 分析软件ANSYS/LS-DYNA，对某型小客车的保险杠系统进行了低速碰撞仿真研究，通过对变形情况，速度，加速度时间历程曲线的结果进行分析研究，对该型保险杠性能的进一步改进提出了建议。     

轿车保险杠耐撞性结构设计的研究

以某型国产轿车保险杠为例 ,建立了保险杠低速碰撞有限元模型。分析了仿真计算中涉及的关键问题。对保险杠系统进行了耐撞性仿真研究 ,指出了保险杠系统设计的基本准则。保险杠低速碰撞试验验证了仿真结果的可靠性。     

基于SolidWorks和LS-DYNA的汽车保险杠低速碰撞仿真研究

以显式动态有限元理论为基础,对汽车保险杠的碰撞进行了计算机模拟研究。用Solidworks建立了汽车保险杠与刚性墙低速碰撞的仿真模型,用ansys对模型进行前处理,调用LS-DYNA求解器进行求解,最后用LS-PROPOSTD做了后处理,得到了保险杠的位移、动能、内能和应力等变化情况,分析结果显示保险杠能吸收大部分能量,对前围件起到了较好的保护作用。     

基于拓扑和形貌优化的泵车连杆优化设计

为了实现泵车连杆轻量化并保证结构稳定性,引入拓扑优化和形貌优化设计方法,在多工况下,以整体屈曲、体积分数和应力为约束,进行连杆优化设计,获得合理的材料分布及加强筋分布,实现结构轻量化,提高了稳定性,为连杆优化设计提供了一种可行且有效的方法。     

耐紫外线的热塑性聚氨酯(TPU)首次用于汽车车身

<正>作为业内首家热塑性聚氨酯(TPU)生产商,巴斯夫成功对材料进行了优化,使其无需涂装即可用于汽车车身。法国汽车制造商标致雪铁龙集团将全新的ElastollanTPU产品AC 55D10 HPM(HPM意为高性能材料)用于制造Airbumps,以保护雪铁龙C4 Cactus的车身。Airbumps是一种采用对比色的大型充气垫保险杠,它们被安装在车身两侧和前后,用以提供撞击和刮擦保护,同时赋予车身以独特外观。这种全球首创的保险杠是雪铁龙与供应商瑞士瑞好和巴斯夫     

A development of simple analysis model on bumper barrier impact and new IIHS bumper impact using the dynamically equivalent beam approach

This paper presents a simple analysis model for bumper barrier impact and new IIHS (Insurance Institute for Highway Safety) bumper impact instead of a non-linear finite element impact analysis. A dynamically equivalent beam approach was introduced to simplify the non-linear dynamic bumper impact. For a bumper barrier impact, the equivalent curved-beam element was substituted for the bumper beam and the bumper foam. For a new IIHS bumper impact, a modified curved-beam element of bumper barrier impact considering the effect of contoured new IIHS impact barrier was used. The accuracy of this simple analysis model was tested by comparing its results with those of the non-linear finite element analysis. Tested bumper beam types were press type beam and roll forming beam used widely in the current car bumpers. The maximum displacement error between the two models did not exceed 1.95% for a barrier impact and 13.2% for a new IIHS bumper impact. This accuracy is good enough to be used in the early stage of bumper beam design process. This simple analysis model is expected to reduce the car development time and tests cost significantly.     

A study on the development of equivalent beam analysis model on pedestrian protection bumper impact

This paper presents a dynamically equivalent beam analysis model on pedestrian protection bumper impact instead of a non-linear finite element impact analysis method. Equivalent beam analysis model was developed by substituting the femur and tibia for dynamically equivalent Euler beam. Dynamically equivalent forces of bumper beam, upper stiffener and lower stiffener are found by a finite element analysis results and applied to the Euler beam model of lower legform impactor. This equivalent beam analysis model was used to obtain a bending angle of lower legform impactor by using finite element beam theory. Peak acceleration of the tibia was obtained by developing an approximate acceleration equation. A linear interpolation of non-linear finite element analysis results considering the dimension variation of bumper beam factors affecting the acceleration was used to get an approximate acceleration equation. The accuracy of this simple analysis model was tested by comparing its results with those of the non-linear finite element analysis. Tested bumper beam types were press type beam and roll forming beam used widely in the current car bumpers. The differences of maximum acceleration of the tibia between the two models did not exceed 10% and the bending angle did not exceed 20%. This accuracy is enough to be used in the early stage of bumper beam design to check the bumper pedestrian performance quickly. Use of equivalent beam analysis model is expected to reduce the analysis time with respect to the non-linear finite element analysis significantly.     

钢铝双帽型保险杠横梁多目标优化

为了保证保险杠横梁优良的碰撞性能,并使其质量更小和结构简单,研究了一种钢铝双帽型保险杠横梁.使用LS-DYNA软件对保险杠横梁进行摆锤正面冲击数值模拟,经对比发现,钢铝双材横梁相比相同结构单一材料的横梁在正面碰撞中显示出良好的平衡性和碰撞性能;使用控制变量法研究发现,横梁前后帽的厚度和法兰的位置对其碰撞性能有显著影响;...     

Analyse non-linéaire et dimensionnement d'une structure de bouclier automobile par couplage calculs–essais

Nonlinear analysis and development of bumper structure of vehicle with a coupled numerical and physical tests. A complete approach for the design of car bumpers loaded by small impacts is presented. It is based on nonlinear explicit dynamic finite element analysis and an experimental procedure to define behaviour laws. This approach is validated by several realistic tests on complex structures under low velocity or quasi-static loading, taking into account geometrical, contact and behaviour nonlinearities.     

ABAQUS刚性分析在乘用车保险杠轻量化上的应用

为降低保险杠产品重量,基于ABAQUS建立轻量化结构保险杠产品的刚性实验模型,验证轻量化乘用车保险杠产品的刚性实验性能,从而为进一步优化产品重量,改善产品结构提供参考指标。     

The effect of leg fracture level and vehicle front-end geometry on pedestrian knee injury and response

In this study a MADYMO (mathematical dynamic modelling) model has been used to identify the influence of leg fracture on the injuries sustained by the pedestrian during front end impact with a vehicle. A factorial study of a MADYMO pedestrian and vehicle model are used to investigate the effect of different leg fracture tolerances, geometry, and vehicle compliance on the criteria measured in the European Enhanced Vehicle-safety Committee (EEVC) pedestrian safety tests. These criteria include knee bending, knee shear response, and lower leg bone (tibia) acceleration. The main study examines the spread of typical values of lower limb tolerance based on reported literature and contrasts the response of weaker, low-strength bones, normal tolerance, and limbs which do not fracture. Results show that knee bending angles and therefore ligament strains are significantly increased when fracture does not occur, and are decreased in bones exhibiting a low-strength response. Bone fracture tolerance is shown to be a significant parameter influencing knee bending. The parameters are compared to show that knee shear is significantly influenced by vehicle bumper compliance and that both criteria are heavily influenced by bumper height. Vehicles with more aggressive geometry, higher bumpers, and larger bumper lead were considered for comparative purposes.     

APPLICATION OF ARCHITECTURE- BASED NEURAL NETWORKS IN MODELING AND PARAMETER OPTIMIZATION OF HYDRAULIC BUMPER

The dynamic working process of 52SFZ-140-207B type of hydraulic bumper is analyzed. The modeling method using architecture-based neural networks is introduced. Using this modeling method, the dynamic model of the hydraulic bumper is established; Based on this model the structural parameters of the hydraulic bumper are optimized with Genetic algorithm. The result shows that the performance of the dynamic model is close to that of the hydraulic bumper, and the dynamic performance of the hydraulic bumper is improved through parameter optimization.