基于正面力传递路径的轿车车身结构耐撞性

Passenger car-body crashworthiness based on the force transmission path of frontal impact

为了提高整车安全性,研究了某轿车车身结构耐撞性。分析了整车正面碰撞过程中碰撞力传递路径,利用HyperWorks软件,建立整车有限元模型,对车身结构关键零件(前纵梁、保险杠横梁和冲撞盒)进行改进设计。利用LS-DYNA软件,根据中国新车评价规程(CNCAP)碰撞安全法规,进行了100%刚性壁(RGB)正面碰撞和40%偏置可变形壁障(ODB)偏置碰撞的数值仿真。结果表明:车身结构改进后,两种碰撞的前围板侵入量明显降低;两侧B柱加速度均减少;碰撞吸能增加(对100%RGB,增加9.8kJ;对40%ODB,增加3.3kJ)。

Structural crashworthiness was investigated for a passenger car-body to improve vehicle safety. The auto-body structure was analyzed based on the force transmission path of frontal impact, with the auto-body finite element model being built using the HyperWorks program and some key parts being improved including the front side rail, front cross rail and crash box for a passenger car-body structure. Two front impacts were numerically simulated using LS-DYNA program according to the crash regulation by China New Car Assessment Program, CNCAP, in which one is full front impact with rigid barrier （RGB） and the other is 40% offset front impact with offset deformable barrier （ODB）. The results show that owing to car-body structure improvements, the intrusion capacities obviously decrease with accelerations of both the left and right ＂B＂ pillars decreasing in the two front impacts, and with increased impact energy absorption of 9.8 kJ for the 100% RGB and 3.3 kJ for the 40% ODB.