Abstract Fluid structure interaction (FSI) problems are often encountered in ocean science and technology. In this present, an implicit immersed boundary (IB) method combined with Lattice Boltzmann Method (LBM) and finite element method (FEM) is presented for the strong-coupled simulations of fluid structure interaction. Velocity field is solved rapidly by lattice Boltzmann-BGK equations without external force, and the deformation of a flexible structure was computed by FEM. Fluid structure coupling was processed by immersed boundary implicit forced method. The resulting combination gives an easy-to-use, inexpensive and accurate technique to solve FSI problems. Simultaneously, the body force on the immersed boundary can be calculated directly and acts as the load for structure solver, so the displacement of structure can be obtained at the same time, which is avoid the time lag between the fluid solver and solid solver. Several examples including flow over a static and deformable plate, and the flow problems of an oscillating and cantilever flexible plate were simulated and analyzed. The results agree well with the previous experimental and numerical investigations, which indicate the IB-LB-FEM proposed in this paper is an efficient and reliable fluid-structure interaction numerical simulation method.

中文翻译：

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一种结合有限元法和格子玻尔兹曼法的强耦合方法，通过隐式浸入边界方案进行流体结构相互作用

摘要 流体结构相互作用（FSI）问题在海洋科学技术中经常遇到。目前，提出了一种结合格子玻尔兹曼方法 (LBM) 和有限元方法 (FEM) 的隐式浸入边界 (IB) 方法，用于流体结构相互作用的强耦合模拟。速度场通过格子Boltzmann-BGK方程在无外力的情况下快速求解，柔性结构的变形通过有限元计算。流固耦合采用浸入边界隐式受迫法处理。由此产生的组合提供了一种易于使用、廉价且准确的技术来解决 FSI 问题。同时，可以直接计算浸入边界上的体力，并作为结构求解器的载荷，这样可以同时获得结构的位移，避免了流体求解器和固体求解器之间的时间滞后。模拟和分析了静态和变形板的流动，以及摆动和悬臂柔性板的流动问题等几个例子。结果与先前的实验和数值研究吻合良好，表明本文提出的IB-LB-FEM是一种高效可靠的流固耦合数值模拟方法。