基于提高后碰性能的车身结构优化

Optimization of Rear Collision Performance Improvement for Automotive Body Structure

为提高乘用车后碰发生时乘客的安全性以及避免燃油泄露,对某款车后纵梁采用分段式设计、合理布置吸能筋及增加后纵梁加强板等优化车身结构设计的方法,使后排R点侵入量由优化前的125mm降低为44mm,最大加速度值由24g降低为18g,加速度峰值时间较优化前延迟5ms,同时同一位置处最大截面力由80kN减小为58kN,后碰性能明显提升。通过CAF仿真分析及实车验证,该设计方法符合法规要求,为处理类似车身结构设计问题提供了参考。

In order to improve the passenger safety in the rear collision and avoid the oil leakage, in this paper, taking a car as an example, its rear longitudinal beam is divided into several parts, the energy absorbing ribs were arranged correctly, and body structure optimization such as the reinforeed panel of rear longitudinal beam is improved, R point intruded from 125 mm decreased to 44 mm, maximum acceleration value from 24 g reduced to 18 g, and the time reaching to acceleration peak delayed 5 ms before optimization. At the same time, the maximum sectional force from 80 kN reduced to 58 kN at the same position, the performance of rear collision is improved significantly. The design method has met the requirement of regulations by CAE and real vehiele validation, it will provide the reference for similar body structure design.