For numerical simulations of ship and offshore hydrodynamic problems, it is challenging to model the interaction between the free surface and moving complex geometries. This paper proposes a discrete-forcing immersed boundary method (IBM) to efficiently simulate moving solid boundaries in incompressible air–water two-phase flows. In the present work, the air–water two-phase flows are modeled using the Volume-of-Fluid (VoF) method. The present IBM is suitable for unstructured meshes. It can be used combined with body-fitted wall boundaries to model the relative motions between solid walls, which makes it flexible to use in practical applications. A field extension method is used to model the interaction between the air–water interface and the immersed boundaries. The accuracy of the method is demonstrated through validation cases, including the three-dimensional dam-break problem with an obstacle, the water exit of a circular cylinder, and a ship model advancing with a rotating semi-balanced rudder. The flow field, free-surface profile and force on the immersed boundaries (IBs) are in good agreement with experimental data and other numerical results.

中文翻译：

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气-水两相流中运动物体的离散强迫浸入边界方法

对于船舶和海上流体动力学问题的数值模拟，建模自由表面和移动复杂几何形状之间的相互作用是一项挑战。本文提出了一种离散强迫沉浸边界方法（IBM），可以有效地模拟不可压缩的气水两相流中的移动固体边界。在目前的工作中，使用流体体积（VoF）方法对空气-水两相流进行建模。当前的IBM适用于非结构化网格。它可以与适合人体的墙边界结合使用，以模拟实体墙之间的相对运动，从而使其在实际应用中具有灵活性。场扩展方法用于模拟空气-水界面与沉浸边界之间的相互作用。通过验证案例证明了该方法的准确性，包括带有障碍物的三维溃坝问题，圆柱体的出水孔以及带有旋转半平衡舵的前进船模型。流场，自由表面轮廓和浸入边界（IBs）上的力与实验数据和其他数值结果非常吻合。