追尾碰撞, 正交试验设计, 综合平衡法, 耐撞性, 结构优化

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A severe consequence could be resulted from an accident due to gas leakage from tank of passenger car in a high speed rear-end impact. This study aimed to improve the crashworthiness of the passenger car in rear-end impact and minimize the risk of gas leakage. Firstly a finite element model of a full-scale car was developed and validated for simulation of a high-speed rear-end impact according to the rules of new FMVSS301. The rear bumper and rail structure were optimized by using OED and comprehensive equilibrium methods. The effects of 4 parameters (thickness and type of material of rear rail and rear bumper) on integrity of fuel system of the car were considered as main design parameters. The main objective of optimization was the maximum effective strain of fuel tank. The secondary objectives were the energy-absorbing capability of rear rail and rear bumper and the deformation of tank structure around. The optimal parameters are as follows: material of rear rail is DP800 with thickness of 1.5mm, material of rear bumper is DP1000 with thickness of 2.0mm. In this configuration the maximum of the effective strain of fuel tank is reduced by 50.07%.The results show parameter optimization of main structure is very usable in improving the crashworthiness of passenger car in the rear-end impact.