We consider a loosely-coupled algorithm for fluid-structure interaction based on a Robin interface condition for the fluid problem (explicit Robin-Neumann scheme). We study the dependence of the stability of this method on the interface parameter in the Robin condition. In particular, for a model problem we find sufficient conditions for instability and stability of the method. In the latter case, we find a stability condition relating the time discretization parameter, the interface parameter, and the fluid and structure densities. Numerical experiments confirm the theoretical findings and highlight optimal choices of the interface parameter that guarantee accurate solutions.

我们考虑基于流体问题的Robin接口条件（显式Robin-Neumann方案）的流固耦合的松耦合算法。我们研究了该方法的稳定性对Robin条件下界面参数的依赖性。特别是，对于模型问题，我们找到了该方法的不稳定性和稳定性的充分条件。在后一种情况下，我们找到了与时间离散化参数，界面参数以及流体和结构密度有关的稳定性条件。数值实验证实了理论发现，并突出了保证准确解决方案的界面参数的最佳选择。