This paper presents a numerical method for the simulation of fluid-structure interaction specifically tailored to interactions between Newtonian fluids and a large number of slender viscoelastic Cosserat rods. Because of their high flexibility and low weight the rods considered here exhibit large deflections, even under moderate fluid loads. Their motion, in turn, modifies the flow so that fluid and structures are strongly coupled to each other which is numerically very challenging. The paper proposes a new coupling approach based on an immersed boundary method which improves upon existing methods for this problem. It is numerically stable and exempt from any global iteration between the fluid part and the structure part, thus yielding high stability and low computational cost of the coupling scheme. The contribution presents the underlying methodology and its algorithmic realization, including an assessment of accuracy and convergence by systematic studies. Various validation cases illustrate performance and versatility of the proposed method.

本文提出了一种数值方法，用于模拟流固耦合，专门针对牛顿流体与大量细长粘弹性Cosserat杆之间的相互作用而设计。由于它们的高柔韧性和低重量，即使在中等流体载荷下，此处考虑使用的杆也显示出较大的挠度。它们的运动进而改变了流动，从而使流体和结构彼此牢固地耦合，这在数值上是非常具有挑战性的。本文提出了一种基于沉浸边界方法的新耦合方法，该方法对现有方法进行了改进。它在数值上是稳定的，并且不受流体部分和结构部分之间的任何全局迭代的影响，因此产生了高稳定性，并且耦合方案的计算成本较低。该文稿介绍了基本的方法及其算法实现，包括通过系统研究评估准确性和收敛性。各种验证案例说明了该方法的性能和多功能性。