Abstract A multiphase flow numerical approach for performing large-eddy simulations of three-dimensional (3D) wave-structure interaction is presented in this study. The approach combines a volume-of-fluid method to capture the air-water interface and a Cartesian cut-cell method to deal with complex geometries. The filtered Navier–Stokes equations are discretised by the finite volume method with the PISO algorithm for velocity-pressure coupling and the dynamic Smagorinsky subgrid-scale model is used to compute the unresolved (subgrid) scales of turbulence. The versatility and robustness of the presented numerical approach are illustrated by applying it to solve various three-dimensional wave-structure interaction problems featuring complex geometries, such as a 3D travelling wave in a closed channel, a 3D solitary wave interacting with a vertical circular cylinder, a 3D solitary wave interacting with a horizontal thin plate, and a 3D focusing wave impacting on an FPSO-like structure. For all cases, convincing agreement between the numerical predictions and the corresponding experimental data and/or analytical or numerical solutions is obtained. In addition, for all cases, water surface profiles and turbulent vortical structures are presented and discussed.

中文翻译：

---

基于笛卡尔切割单元的多相流模型，用于三维波结构相互作用的大涡模拟

摘要 本研究提出了一种用于执行三维 (3D) 波-结构相互作用的大涡模拟的多相流数值方法。该方法结合了流体体积法来捕获空气-水界面和笛卡尔切割单元法来处理复杂的几何形状。过滤后的 Navier-Stokes 方程通过有限体积法和用于速度-压力耦合的 PISO 算法进行离散，动态 Smagorinsky 子网格尺度模型用于计算湍流的未解析（子网格）尺度。通过将其应用于解决具有复杂几何形状的各种三维波-结构相互作用问题，例如封闭通道中的 3D 行波，与垂直圆柱相互作用的 3D 孤立波，与水平薄板相互作用的 3D 孤立波，以及影响 FPSO 类结构的 3D 聚焦波。对于所有情况，在数值预测和相应的实验数据和/或解析或数值解之间获得令人信服的一致性。此外，对于所有情况，都提出并讨论了水面剖面和湍流涡旋结构。