某乘用车正面碰撞仿真分析

Simulation analysis of frontal collision for a passenger car

为准确评价整车正面碰撞过程中的碰撞安全性能,采用CATIA软件建立整车几何模型,导入HyperMesh软件搭建整车有限元模型,结合LS-DYNA软件模拟汽车正面碰撞,并采用HyperMesh软件分析模型可靠性及碰撞过程中整车变形、B柱加速度、各部件变形等。仿真结果表明:整车碰撞期间,增加质量与总质量的比为2.16%,沙漏能与总能量的比为1.02%,整车模型可靠性满足要求;左右两侧B柱最大加速度分别约为42.5 g(g为自由落体加速度)、45.4 g,满足中国新车评价规程中两侧B柱最大加速度不得超过72 g的要求;该车前防撞梁最大变形为178.1 mm,前吸能盒最大变形为315.9 mm,前纵梁最大变形为618.9 mm,该车前部吸能部件具有良好的吸能效果;前围板最大变形为137.8 mm,满足碰撞试验前围板最大变形不超过150 mm的限值要求,可以保护驾驶员及乘客的安全。

To accurately assess the safety performance of a vehicle during a frontal collision,a geometric model of the entire vehicle is established using CATIA software.The finite element model of the entire vehicle is built using HyperMesh software,and the frontal collision is simulated using LS-DYNA software.HyperMesh software is then used to analyze the reliability of the model as well as the deformation of the entire vehicle,B-pillar acceleration,and the deformation of various components during the collision.The simulation results indicate that during the collision,the ratio of added mass to total mass is 2.16%,and the ratio of hourglass energy to total energy is 1.02%,meeting the reliability requirements of the vehicle model.The maximum accelerations of the left and right B-pillars are 42.4 g and 45.4 g,respectively,satisfying the China New Car Assessment Program′s requirement that the maximum acceleration of the B-pillars on both sides should not exceed 72 g.The maximum deformation of the front bumper beam is 178.1 mm,the maximum deformation of the front energy absorber box is 315.9 mm,and the maximum deformation of the front longitudinal beam is 618.9 mm,which indicates that the front energy-absorbing components of the vehicle have good energy-absorbing effects.The maximum deformation of the front bulkhead is 137.8 mm,meeting the collision test limit of a maximum deformation of no more than 150 mm,which better protects the safety of the driver and passengers.