Design of architected functional materials that possess desired damping performance is a topic of great interest in both academic research and industrial applications. This study investigates the concept of ‘directional damping’ for viscoelastic composites and develops a topology optimization framework to achieve directional damping design. Microstructures with both load-bearing capacity and dominant damping in the prescribed direction are obtained by maximizing the loss factor while imposing stiffness constraints. An optimized directional damping microstructure design exhibits a loss factor 1.8 times higher than the isotropic design in the prescribed direction. It is found that the optimized configurations with curved viscoelastic strips are similar to wavy ‘suture’ lines in the beaks of woodpeckers, which possess outstanding energy absorption performance. We have also verified the superiority of the directional damping design through numerical simulations and experiments of the microstructured composites. The experiment results show significant reduction of peak response for the directional damping design compared to the isotropic counterpart. To demonstrate the application potential of the optimized unit cell microstructures, a novel conceptual airless tire that exhibits improved stiffness and shock absorption performance is designed and validated through both numerical simulations and experiments.

中文翻译：

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通过拓扑优化进行粘弹性复合材料的定向阻尼设计

具有所需阻尼性能的建筑功能材料的设计是学术研究和工业应用都非常感兴趣的话题。本研究研究了粘弹性复合材料的“方向阻尼”概念，并开发了拓扑优化框架来实现方向阻尼设计。通过在施加刚度约束的同时最大化损耗因子，可以获得在指定方向上具有承载能力和主导阻尼的微结构。优化的定向阻尼微结构设计在指定方向上的损耗因子比各向同性设计高 1.8 倍。研究发现，弯曲粘弹性条的优化配置类似于啄木鸟喙部的波浪“缝合”线，具有出色的能量吸收性能。我们还通过微结构复合材料的数值模拟和实验验证了定向阻尼设计的优越性。实验结果表明，与各向同性设计相比，定向阻尼设计的峰值响应显着降低。为了展示优化的晶胞微观结构的应用潜力，通过数值模拟和实验设计并验证了一种新颖的概念性无气轮胎，该轮胎具有更高的刚度和减震性能。