Robin boundary conditions are a natural consequence of employing Nitsche's method for imposing the kinematic velocity constraint at the fluid-solid interface. Loosely-coupled FSI schemes based on Dirichlet-Robin or Robin-Robin coupling have been demonstrated to improve the stability of such schemes with respect to added-mass. This paper aims to offer some numerical insights into the performance characteristics of such loosely-coupled FSI schemes based on Robin boundary conditions. Using numerical examples, we demonstrate that the improved stability due to the added damping term is actually at the expense of important dynamic characteristics of the structural sub-problem.

中文翻译：

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基于 Robin 边界条件的松耦合 FSI 方案的性能洞察

Robin 边界条件是采用 Nitsche 方法在流固界面施加运动速度约束的自然结果。基于 Dirichlet-Robin 或 Robin-Robin 耦合的松散耦合 FSI 方案已被证明可以提高此类方案在附加质量方面的稳定性。本文旨在对这种基于 Robin 边界条件的松散耦合 FSI 方案的性能特征提供一些数值见解。使用数值例子，我们证明了由于增加的阻尼项而提高的稳定性实际上是以牺牲结构子问题的重要动态特性为代价的。