当前位置: X-MOL 学术Struct. Multidisc. Optim. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Stress-constrained optimization using graded lattice microstructures
Structural and Multidisciplinary Optimization ( IF 3.9 ) Pub Date : 2020-10-05 , DOI: 10.1007/s00158-020-02723-z
Dilaksan Thillaithevan , Paul Bruce , Matthew Santer

In this work, we propose a novel method for predicting stress within a multiscale lattice optimization framework. On the microscale, a scalable stress is captured for each microstructure within a large, full factorial design of experiments. A multivariate polynomial response surface model is used to represent the microstructure material properties. Unlike the traditional solid isotropic material with a penalization-based stress approach or using the homogenized stress, we propose the use of real microscale stress components with macroscale strains through linear superposition. To examine the accuracy of the multiscale stress method, full-scale finite element simulations with non-periodic boundary conditions were performed. Using a range of microstructure gradings, it was determined that 6 layers of microstructures were required to achieve periodicity within the full-scale model. The effectiveness of the multiscale stress model was then examined. Using various graded structures and two load cases, our methodology was shown to replicate the von Mises stress in the center of the unit lattice cells to within 10% in the majority of the test cases. Finally, three stress-constrained optimization problems were solved to demonstrate the effectiveness of the method. Two stress-constrained weight minimization problems were demonstrated, alongside a stress-constrained target deformation problem. In all cases, the optimizer was able to sufficiently reduce the objective while respecting the imposed stress constraint.



中文翻译:

使用梯度晶格微结构的应力约束优化

在这项工作中,我们提出了一种在多尺度晶格优化框架内预测应力的新颖方法。在微观尺度上,在大型的全因子设计实验中,为每个微观结构捕获了可扩展的应力。多元多项式响应面模型用于表示微结构材料的性能。与基于惩罚的应力方法或使用均质应力的传统固体各向同性材料不同,我们建议通过线性叠加使用真正的微观应力分量和宏观应变。为了检查多尺度应力方法的准确性,在非周期性边界条件下进行了满量程有限元模拟。使用一系列的微观结构等级,已确定需要6层微结构才能在完整模型中实现周期性。然后检查了多尺度应力模型的有效性。通过使用各种渐变结构和两个荷载工况,我们的方法被证明可以将大多数测试用例中单位晶格中心的von Mises应力复制到10%以内。最后,解决了三个应力约束优化问题,以证明该方法的有效性。演示了两个应力约束的重量最小化问题以及应力约束的目标变形问题。在所有情况下,优化器都能够在遵守施加的应力约束的同时充分降低目标。通过使用各种渐变结构和两个荷载工况,我们的方法被证明可以将大多数测试用例中单位晶格中心的von Mises应力复制到10%以内。最后,解决了三个受应力约束的优化问题,以证明该方法的有效性。演示了两个应力约束的重量最小化问题以及应力约束的目标变形问题。在所有情况下,优化器都能够在遵守施加的应力约束的同时充分降低目标。使用各种渐变结构和两个荷载工况,我们的方法论证明可以在大多数测试用例中将晶格中心的von Mises应力复制到10%以内。最后,解决了三个应力约束优化问题,以证明该方法的有效性。演示了两个应力约束的重量最小化问题以及应力约束的目标变形问题。在所有情况下,优化器都能够在遵守施加的应力约束的同时充分降低目标。解决了三个应力约束优化问题,以证明该方法的有效性。演示了两个应力约束的重量最小化问题以及应力约束的目标变形问题。在所有情况下,优化器都能够在遵守施加的应力约束的同时充分降低目标。解决了三个应力约束优化问题,以证明该方法的有效性。演示了两个应力约束的重量最小化问题以及应力约束的目标变形问题。在所有情况下,优化器都能够在遵守施加的应力约束的同时充分降低目标。

更新日期:2020-10-05
down
wechat
bug