In this paper, we develop a "modified" immersed finite element method (mIFEM), a non-boundary-fitted numerical technique, to study fluid-structure interactions. Using this method, we can more precisely capture the solid dynamics by solving the solid governing equation instead of imposing it based on the fluid velocity field as in the original immersed finite element (IFEM). Using the IFEM may lead to severe solid mesh distortion because the solid deformation is been over-estimated, especially for high Reynolds number flows. In the mIFEM, the solid dynamics is solved using appropriate boundary conditions generated from the surrounding fluid, therefore produces more accurate and realistic coupled solutions. We show several 2-D and 3-D testing cases where the mIFEM has a noticeable advantage in handling complicated fluid-structure interactions when the solid behavior dominates the fluid flow.

中文翻译：

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用于全耦合流固耦合的改进浸入式有限元法


在本文中，我们开发了一种“改进的”浸入式有限元方法（mIFEM），这是一种非边界拟合数值技术，用于研究流体-结构相互作用。使用这种方法，我们可以通过求解固体控制方程来更精确地捕获固体动力学，而不是像原始浸入式有限元 (IFEM) 中那样基于流体速度场强加固体动力学。使用 IFEM 可能会导致严重的实体网格变形，因为实体变形被高估，尤其是对于高雷诺数流动。在 mIFEM 中，使用周围流体生成的适当边界条件来求解固体动力学，因此产生更准确、更真实的耦合解。我们展示了几个 2-D 和 3-D 测试案例，其中当固体行为主导流体流动时，mIFEM 在处理复杂的流体-结构相互作用方面具有明显的优势。