Numerical wave tank study of extreme waves and wave-structure interaction using OpenFoam®

In the present work, the open source Computational Fluid Dynamics (CFD) package-Open Field Operation and Manipulation (OpenFoam®) is used to simulate wave-structure interactions and a new wave boundary condition is developed for extreme waves. The new wave boundary condition is implemented for simulation of interaction with a fixed/floating truncated cylinder and a simplified Floating Production Storage and Offloading platform (FPSO) and results are compared with physical experiment data obtained in the COAST laboratory at Plymouth University. Different approaches to mesh generation (i.e. block and split-hexahedra) are investigated and found to be suitable for cases considered here; grid and time convergence is also demonstrated. The validation work includes comparison with theoretical and experimental data. The cases performed demonstrate that OpenFoam® is capable of predicting these cases of wave-structure interaction with good accuracy (e.g. the value of maximum pressure on the FPSO is predicted within 2.4% of the experiment) and efficiency. The code is run in parallel using high performance computing and the simulations presented have shown that OpenFoam® is a suitable tool for coastal and offshore engineering applications, is able to simulate two-phase flow in 3D domains and to predict wave-structure interaction well.