铝泡沫填充薄壁结构耐撞可靠性优化设计

Crashworthiness Reliability Design Optimization of Aluminum Foam Filled Thin-wall Structures

泡沫填充薄壁结构能有效地改善汽车薄壁吸能部件的耐撞性。为设计更轻与更有效的吸能结构,并满足汽车安全性设计要求,提出一种新颖的轻质铝泡沫填充双管薄壁结构,并对其耐撞性展开确定性最优化设计。但是,由于薄壁结构的厚度、屈服强度以及铝泡沫的密度等设计参数易受到仿真以及制造误差等不确定性因素的影响,导致确定性最优解收敛于约束边界,从而丢失了应有的使用可靠性要求。因此,提出基于Kriging近似模型与一阶可靠性分析方法的铝泡沫填充结构可靠性最优设计方法,并进一步开展基于参数不确定性的铝泡沫填充结构的耐撞性可靠性优化设计研究。优化结果显示,可靠性最优解不仅远离约束边界,而且较好地满足了铝泡沫填充结构的安全性与可靠性设计要求。

Foam filled thin-wall structures can effectively improve the crashworthiness of automobile thin-walled element.To design more efficient and lighter absorber structures and meet the safety design demand,a novel aluminum foam filled double square structure is presented,and deterministic optimum design of energy absorption characteristic is preformed for aluminum foam filled structures.However,the design parameters,such as the thickness,yield stress of thin wall and density of aluminum foam,can often have uncertainties in simulation and manufacturing process,it can make the deterministic optimal solution convergence to the design constraint boundaries,and lose the reliable design demand.Hence,reliability design optimization scheme based on kriging approximate models and first order reliability method is presented.Finally,reliability design optimization with parameters uncertainties of aluminum foam filled structures is performed.The optimal results show that the reliability optimal solutions not only are far from the constraint boundaries,but also better meet the safety and reliability of aluminum foam filled structure design demand.