基于正面碰撞汽车前纵梁结构优化设计分析  

Optimization Design Analysis of Front Longitudinal Beam Structure Based on Frontal Collision

作　　者：赵世婧[1] 樊继红[2] 王贞涛[3] ZHAO Shi-jing;FAN Ji-hong;WANG Zhen-tao(Suzhou Polytechnic Institute Agriculture,Jiangsu Suzhou 215008,China;China National Intellectual Property Administration,Beijing 100088,China;School of Energy and Power Engineering,Jiangsu University,Jiangsu Zhenjiang 212013,China)

机构地区：[1]苏州农业职业技术学院,江苏苏州215008 [2]国家知识产权局专利局,北京100088 [3]江苏大学能源与动力工程学院,江苏镇江212013

出　　处：《机械设计与制造》2020年第12期138-141,共4页Machinery Design & Manufacture

基　　金：国家自然科学基金青年基金项目(51106064)。

摘　　要：汽车发生正面碰撞时,前纵梁和防撞梁组成的吸能结构的承载能力直接影响到整车的安全性能。根据前纵梁的结构特点和碰撞吸能过程的变形特征,建立前纵梁的有限元分析模型;对前纵梁在吸能过程中的失效形式进行分析;压溃失效和折弯失效是两种主要的失效形式;折弯失效发生时,前纵梁失去原有的设计吸能作用,而临界角是发生折弯变形的最要指标;针对影响前纵梁折弯变形临界角的主要因素进行分析,包括长宽比、材料厚度、壁障摩擦系数等,获得结构参数对性能的影响规律;根据影响规律对某汽车前纵梁结构进行优化设计,并采用落锤压溃试验对结构优化前后的性能进行对比分析。结果可知:前纵梁发生弯曲变形时存在临界角度,对轴向承载影响较大;前纵梁的长宽比、壁障接触面摩擦系数是影响临界角度的重要因素;材料厚度的影响较小;降低长宽比,增大摩擦系数,在相同的倾角下,前纵梁弯曲承载变形能力提高,同时梁体轻量化13.7%;试验验证表明分析结果和优化设计的准确性,研究结果为此类设计提供参考。When a frontal collision occurs,the load capacity of the energy absorbing structure of the front longitudinal beam and anti-collision beam will directly affect the safety performance of the vehicle.According to the structural characteristics of the front longitudinal beam and the deformation characteristics during the collision energy absorption process,the finite element analysis model of the front longitudinal beam is established.The failure form of the front longitudinal beam during the energy absorption process is analyzed.Crush failure and bend failure are the two main failure modes.The front longitudinal beam loses its original design energy absorption function when bending failure occurs,and the critical angle is the most important index for the occurrence of bending deformation.The main factors affecting the critical angle of the front longitudinal beam bending deformation are analyzed,such as aspect ratio,material thickness,barrier friction coefficient,etc.,and the influence of structural parameters on performance is obtained.According to the law of influence,the front girder structure of an automobile is optimized.And the performance before and after structural optimization is compared and analyzed by using drop hammer crushing test.The results show that there is a critical angle the front longitudinal beam is bent and deformed,which has a great influence on the axial load.The length to width ratio of the front longitudinal beam and the friction coefficient of the wall contact surface are the important factors affecting the critical Angle.The effect of material thickness is small.The bending capacity of the front longitudinal beam is improved by reducing the aspect ratio and increasing the friction coefficient under the same inclination angle,and the beam body is lightly weighted by 13.7%.Test verification shows the accuracy of the analysis results and the optimization design,and the research results provide a reference for such design.

关 键 词：汽车 前纵梁 折弯变形 吸能 落锤压溃试验 

分 类 号：TH16[机械工程—机械制造及自动化] U461.8[机械工程—车辆工程]