基于OLC拐点的车体结构较优设计

基于OLC理论,研究了正面碰撞中车体结构设计与乘员损伤的关联性.基于56 km/h正面刚性壁障(Frontal Rigid Barrier,FRB)碰撞工况,通过二阶波简化得到一阶加速度a1、二阶加速度a2、动态位移D三个车体结构设计指标.分析了不同车体结构设计指标与OLC的关系,发现在D不变的情况下,当a1≤215....

Optimal Design of Vehicle Body Structure Based on OLC Inflection Point Phenomenon

Based on OLC theory,the correlation between car body structure design and occupant injury in frontal collisions was studied.Firstly,the three design indexes,i.e.the first-order acceleration a1,the second-order acceleration a2 and the dynamic displacement D were obtained by simplifying the second-order wave under the collision condition of 56 km/h FRB.Then the relationship between OLC and the design indexes of the car body structure was analyzed.It was found that when a1≤215.82 m/s² and D is a constant,the OLC shows a decreasing trend with the increase of a1.For a1>215.82 m/s²,the OLC shows an increasing trend and has an obvious inflection point.When a1 is unchanged,the OLC will decrease with the decrease of D.Finally,based on the benchmarking model,the occupant injuries for different body structure design indexes were analyzed.It is found that the trend in occupant injury is consistent with the change in OLC,with an inflection point as well.The linear fitting is used and the coefficient of determination R2 between the occupant injury and OLC is 0.95.In order to test the universality of“inflection point phenomenon”,the collision condition of 50 km/h FRB is applied and the same conclusion is reached.Finally the body structure design of a certain car model is guided by the results obtained.