Efficient Inverse-designed Structural Infill for Complex Engineering Structures: De-homogenization results

Exodus II hex mesh data files of unstructured de-homogenization results from the paper "Efficient Inverse-designed Structural Infill for Complex Engineering Structures". The mesh files have side sets for applied load case and boundary conditions. The load cases and boundary conditions are found in the paper. The data set contains the results of the three models used in the paper: the Michell cantilever, the Lotte tower, and the GE Jet Engine Bracket.Abstract cited from DOI: https://doi.org/10.48550/arXiv.2307.09518 :<br>"Inverse design of high-resolution and fine-detailed 3D lightweight mechanical structures is notoriously expensive due to the need for vast computational resources and the use of very fine-scaled complex meshes. Furthermore, in designing for additive manufacturing, infill is often neglected as a component of the optimized structure. In this paper, both concerns are addressed using a de-homogenization topology optimization procedure on complex engineering structures discretized by 3D unstructured hexahedrals. Using a rectangular-hole microstructure (reminiscent to the stiffness optimal orthogonal rank-3 multi-scale) as a base material for the multi-scale optimization, a coarse-scale optimized geometry can be obtained using homogenization-based topology optimization. Due to the microstructure periodicity, this coarse-scale geometry can be up-sampled to a fine physical geometry with optimized infill, with minor loss in structural performance and at a fraction of the cost of a fine-scale solution. The upsampling on 3D unstructured grids is achieved through stream surface tracing which aligns with the optimized local orientation. The periodicity of the physical geometry can be tuned, such that the material serves as a structural component and also as an efficient infill for additive manufacturing designs. The method is demonstrated through three examples. It achieves comparable structural performance to state-of-the-art methods but stands out for its significant computational time reduction, much faster than the base-line method. By allowing multiple active layers, the mapped solution becomes more mechanically stable, leading to an increased critical buckling load factor without additional computational expense. The proposed approach achieves promising results, benchmarking against large-scale SIMP models demonstrates computational efficiency improvements of up to 250 times."<br>

本数据集为论文《面向复杂工程结构的高效逆向设计结构填充》（Efficient Inverse-designed Structural Infill for Complex Engineering Structures）所得到的非均匀化（de-homogenization）结果的Exodus II非结构化六面体网格（hex mesh）数据文件。该网格文件附带用于施加载荷工况与边界条件的边集（side sets），论文中已详述所用载荷工况与边界条件。本数据集涵盖该论文中使用的三类模型的计算结果：米契尔悬臂梁（Michell cantilever）、洛特塔（Lotte tower）以及通用电气喷气发动机支架（GE Jet Engine Bracket）。

引用自DOI: https://doi.org/10.48550/arXiv.2307.09518 的摘要如下：
"由于需要海量计算资源并采用极精细的复杂网格，高分辨率、细粒度三维轻量化机械结构的逆向设计向来成本高昂。此外，在面向增材制造（additive manufacturing）的结构设计中，填充结构常被作为优化结构的组成部分而遭到忽视。本文针对由三维非结构化六面体单元离散化的复杂工程结构，采用非均匀化拓扑优化（topology optimization）流程解决了上述两大问题。本文采用矩形孔微结构（其性能类似刚度最优正交秩3多尺度模型）作为多尺度优化的基础材料，通过基于均匀化（homogenization）的拓扑优化可得到粗尺度优化几何。得益于微结构的周期性，该粗尺度几何可被上采样至带有优化填充结构的精细物理几何，且结构性能损失极小，所需成本仅为精细尺度求解方案的一小部分。针对三维非结构化网格的上采样通过与优化后局部取向对齐的流线追踪（stream surface tracing）实现。可对物理几何的周期性进行调整，使得该材料既可作为结构构件，又可作为增材制造设计中的高效填充结构。本文通过三个示例验证了所提方法的有效性。该方法的结构性能可与当前主流方法相媲美，但其显著缩短了计算耗时，远快于基线方法。通过允许多个活性层，映射得到的解在机械稳定性上更为优异，无需额外计算开销即可提升临界屈曲载荷系数（buckling load factor）。所提方法取得了极具前景的结果，与大型SIMP（Solid Isotropic Material with Penalization，实体各向同性惩罚法）模型进行基准测试表明，其计算效率提升最高可达250倍。"