有利于行人保护的非对称式发动机罩盖的设计

Design of asymmetric vehicle hood inner for pedestrian head protection

轿车—行人碰撞中,发动机罩盖是造成行人头部伤害的主要来源。该文进行了6组轿车—儿童行人头型冲击器冲击试验,建立了相应的冲击试验有限元模型(FEM),并完成了模型标定。通过FEM仿真,分析了5种不同内板肋板结构的发动机内罩板吸能特性;并根据某款发动机舱布置,设计了一种非对称式发动机罩盖内罩板;进行了有限元模型验证。结果显示:优化设计后,罩盖的多个冲击点的头部伤害标准HIC值降至1300以下,部分冲击点降至1000以下。因而,明显提升了该种发动机罩盖对行人头部保护。

Engine hoods are a main resource of pedestrian head injuries in vehicle-pedestrian impact. Six tests were made using child pedestrian head impactors, with the corresponding finite element model built and calibrated to improve pedestrian head protection. The energy absorption performances of five types of hood inner structures were analyzed using a finite element model （FEM）, with an asymmetric vehicle hood inner then designed according to the engine compartment layout of a kind of vehicle. The results show that the head injury criterion （HIC） at several areas of the hood inner is reduced to less than 1300, a few of which to less than 1000. Therefore, the pedestrian head protection is significantly improved using the asymmetric vehicle hood inner.