基于Kriging代理模型的大直径运载火箭蒙皮桁条结构分步优化方法研究

Substep Optimization Method of Skinned Truss Structure for Large Diameter Launch Vehicle Based on Kriging Surrogate Model

针对大直径运载火箭结构轻质优化设计,开展轴压作用下的蒙皮桁条结构优化方法研究。首先采用显式非线性动力学算法进行静稳定性分析,获得蒙皮桁条结构的后屈曲失稳路径;然后根据蒙皮桁条结构特点,基于Kriging代理模型和组合优化算法的分步优化策略;最后针对中间框和不同截面形式的桁条开展参数优化研究,确立了蒙皮桁条结构最优设计方案。结果表明:“Π”型桁条的承载效率较高,最终优化结果对大型蒙皮桁条结构减重效果明显。

Taking the lightweight optimization design of large-diameter launch vehicle as the research background,the optimization method of the skinned truss structure under axial compression was studied.First,the explicit nonlinear dynamics algorithm was used to analyze the static stability of the skinned truss structure,and the post-buckling instability path of the structure was obtained.Then,according to the structure characteristics,a substep optimization strategy based on Kriging surrogate model and combinatorial optimization algorithm was proposed.The parameter optimization research was carried out for the middle frames and trusses.Consequently,the optimal design scheme of the structure was obtained.The results showed that the load-bearing efficiency of the“Π”type truss was higher.The optimization strategy achieved obvious weight reduction effect which verified the effectiveness of the method.