In this work, a non-reflective boundary condition, the Perfectly Matched Layer (PML) technique, is adapted and implemented in a fluid-structure interaction numerical framework to demonstrate that proper boundary conditions are not only necessary to capture correct wave propagations in a flow field, but also its interacted solid behavior and responses. While most research on the topics of the non-reflective boundary conditions are focused on fluids, little effort has been done in a fluid-structure interaction setting. In this study, the effectiveness of the PML is closely examined in both pure fluid and fluid-structure interaction settings upon incorporating the PML algorithm in a fully-coupled fluid-structure interaction framework, the Immersed Finite Element Method. The performance of the PML boundary condition is evaluated and compared to reference solutions with a variety of benchmark test cases including known and expected solutions of aeroacoustic wave propagation as well as vortex shedding and advection. The application of the PML in numerical simulations of fluid-structure interaction is then investigated to demonstrate the efficacy and necessity of such boundary treatment in order to capture the correct solid deformation and flow field without the requirement of a significantly large computational domain.

中文翻译：

---

使用浸入有限元法的流体-结构相互作用的完美匹配层吸收边界


在这项工作中，在流体-结构相互作用数值框架中采用和实现了非反射边界条件，即完美匹配层 (PML) 技术，以证明适当的边界条件不仅是捕获流中正确的波传播所必需的场，而且还包括其相互作用的固体行为和反应。虽然大多数关于非反射边界条件主题的研究都集中在流体上，但在流体-结构相互作用设置方面却很少做出努力。在这项研究中，将 PML 算法合并到完全耦合的流固耦合框架（浸入式有限元法）中，在纯流体和流固耦合设置中仔细检查了 PML 的有效性。使用各种基准测试用例评估 PML 边界条件的性能，并将其与参考解决方案进行比较，其中包括气动声波传播以及涡旋脱落和平流的已知和预期解决方案。然后研究 PML 在流固耦合数值模拟中的应用，以证明这种边界处理的有效性和必要性，以便在不需要很大的计算域的情况下捕获正确的固体变形和流场。