This study presents an efficient numerical framework for simulating fluid–structure interactions (FSIs) involving flexible, lightweight shells subjected to high-Reynolds-number flows. By combining the immersed boundary method (IBM) and isogeometric analysis (IGA), the framework incorporates three major innovations: (1) a wall-modeling, direct-forcing, diffused-interface IBM tailored for FSI simulations with high-Reynolds-number turbulent flows, employing non-equilibrium explicit wall functions; (2) integration of the interface quasi-Newton inverse least-squares (IQN-ILS) method into the IBM/IGA framework to enhance the accuracy and efficiency of iterative Gauss–Seidel coupling in strongly coupled FSI scenarios; and (3) high-order solvers for both fluid and structural domains, featuring a sixth-order compact finite difference method (FDM) for fluid dynamics and isogeometric shell formulations for structural analysis. The framework is validated through four numerical test cases, including simulations of a hinged flag, an inverted flag, a membrane airfoil, and an air-supported membrane structure. The results demonstrate good agreement with reference data, showing the framework’s efficiency, accuracy, and applicability for solving large-scale shell-related FSI problems across diverse engineering and scientific domains.

中文翻译：

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高雷诺数流中柔性壳和轻壳流中柔性壳和轻壳流固耦合的浸没边界法和等几何壳分析的耦合


本研究提出了一个高效的数值框架，用于模拟流-固耦合 （FSI），该框架涉及受高雷诺数流动影响的柔性、轻质壳。通过结合浸没边界法 （IBM） 和等几何分析 （IGA），该框架融合了三大创新：（1） 壁建模、直接强制、扩散界面 IBM，专为高雷诺数湍流的 FSI 仿真量身定制，采用非平衡显式壁函数;（2） 将界面准牛顿逆最小二乘法 （IQN-ILS） 方法集成到 IBM/IGA 框架中，以提高强耦合 FSI 情景中迭代高斯-塞德尔耦合的准确性和效率;（3） 流体和结构域的高阶求解器，具有用于流体动力学的六阶紧缩有限差分法 （FDM） 和用于结构分析的等几何壳公式。该框架通过四个数值测试用例进行验证，包括铰链旗、倒旗、膜翼型和空气支撑膜结构的模拟。结果表明与参考数据具有良好的一致性，表明该框架在解决不同工程和科学领域的大规模 shell 相关 FSI 问题方面的效率、准确性和适用性。