腿式着陆器用不同拓扑结构金属蜂窝吸能特性优化设计

Crashworthiness optimization of different topological structures of metal honeycomb used in a legged-typed lander

作为一种多孔固体材料的,由于其结构和功能的特殊性,金属蜂窝在缓冲吸能领域应用广泛。为了得到不同拓扑结构下金属蜂窝的异面压缩特性及缓冲特性,为其用于缓冲吸能领域提供依据,应用数值仿真软件Patran/DYNA对5种不同拓扑结构的金属蜂窝进行了压缩仿真。由于蜂窝结构的多样性,基于PCL语言编写金属蜂窝参数化有限元分析程序,实现有限元模型自动建立。采用全因素实验设计法对仿真点进行了规划,基于仿真结果,使用响应面方法建立了金属蜂窝吸能特性的近似函数模型,并分析模型精度。以金属蜂窝比吸能为优化目标,蜂窝主要结构参数为设计变量,针对腿式着陆器用金属蜂窝缓冲结构进行了优化设计,结果表明正六边形金属蜂窝在五种蜂窝结构中吸能效果最优。

Honeycomb, as one kind of cellular structures, is widely used in buffers for its structural and functional properties. To provide a basis for metal honeycomb used as buffering and crashworthy structures, out-of-plane compressive and energy-absorption properties of different topological structures of metal honeycomb were investigated here. Numerical compression simulations for topological structures of metal honeycomb were made using Patran/DYNA software. The numerical models were used here with various lengths and foil thicknesses of honeycomb cell, PCL language provided a convenience to automatically accommodate the parametrized FE model to different designs. Full factoral design was employed to get simulation points, surrogate models were obtained from simulation results based on the response surface method and the accuracy of the models was analyzed. By referring to a classic lunar lander, the specific energy absorption was set as the design objective for obtaining the optimal topological metal honeycomb structure used as the energy absorber. The optimization results showed that hexagonal metal honeycomb characterized the best specific energy absorption in the five topological structures of metal honeycomb.