基于柔性腿型的轿车前部吸能结构研究

Study on sedan frontal energy absorbing structural based on Flex-PLI

针对轿车前端吸能结构与柔性腿碰撞伤害值的问题,对轿车前端吸能部件结构与材料进行了研究。通过运用计算机辅助工程技术,建立了某轿车以及泡沫吸能结构和薄壁钢吸能结构有限元模型;轿车前端分别采用了两种吸能结构,并改变了吸能结构的压溃空间,与柔性腿仿真模型进行了碰撞实验;通过实验数据分析、对比了两种吸能结构与柔性腿相撞的特点。实验结果表明,汽车前端吸能结构使用泡沫材料,适当减小泡沫厚度,有利于降低柔性腿韧带伸长量;吸能结构使用薄壁钢结构则需要足够的吸能空间,有利于调整碰撞腿型运动姿态,降低柔性腿胫骨弯矩及韧带伸长量;薄壁钢结构刚度均匀且具有金属的压溃特性,在与行人腿部相撞时,可以起到更好的保护作用。

Aiming at car frontal energy absorption structure and flexible legs collision damage,structures and materials of car frontal energyabsorbing components were studied. Finite element model of a sedan,as well as foam energy absorption structure and thin-wall steel energy structure were established,by using the computer-aided engineering（ CAE） technique. Collision experiments were developed by car frontal components and flexible legs,with two kinds of energy absorption structure adopted by automobile front-end,and the energy absorption space was changed. Characteristics of collision of two different energy absorption structures were analyzed and compared by experimental data with Flex-PLI. The results indicate that car frontal energy absorption structures use foam,thickness of the foam are reduced,which are beneficial to reduce ligaments elongations of the Flex_ PLI. And thin-walled steel are used as energy absorption structures,which enough energy absorption space can adjust the movement attitude of the legform,and reduce ligaments elongations as well as tibia bending moment of the Flex_PLI. The thin-walled steel stiffness is uniformity with crumple characteristics,when a collision,pedestrians legs can be better protected.