车辆碰撞计算机模拟分析与评价

针对某型轿车进行了正面和侧面碰撞计算机模拟分析与评价.建立了含50百分位的HybridⅢ型假人及安全带约束系统的整车有限元模型,根据动态非线性有限元法的基本原理,建立碰撞过程描述方程和结构有限元离散化方程.在LS-DYNA环境下,对整车集成系统进行了正面和侧面碰撞的数值模拟和分析,求解出了碰撞时整车位移、速度和加速时间,并分析了该车在碰撞过程中主要吸能部件的吸能效果及能量与力的传播途径,以及假人的伤害程度.仿真结果表明,含假人的汽车碰撞过程计算机模拟,不仅能预测汽车结构本身的耐撞性能,还能较准确地预测碰撞过程中乘员的响应与伤害程度,对于减少实车碰撞试验次数,加快新车型开发速度具有重要意义.

Simulation and Evaluation of Vehicle's Impact

The frontal and side impact of a car were simulated and the whole body response and injury of passanger thus caused were evaluated on computer. FEA models were developed for the whole car in which the space occupied by the 50th percentile Hybrid III dummy and safety-belt restraint system. According to the basic principle of dynamic non-linear FEM, an equation describing the impact process and FEA discretization equation are given. The frontal and side impact of the integrated system of the whole car is numerically simulated and analyzed by the software LS-DYNA, then the time curves of displacement, speed and acceleration for car during impact are solved, as well as the effect of the main energy-absorbing parts, the energy/force transmitting path and the injury level of dummy due to impact. Simulation results revealed that such a simulation will predict not only the crashworthiness of the car but also the passengers' response and injury level comparatively accurately during its collision. It will be of significance to reducing the number of impact tests and expediting the R and D of new type/model of cars.