A 3D Hybrid Model Coupling SPH and QALE-FEM for Simulating Nonlinear Wave-structure Interaction

摘要

This paper presents a three-dimensional hybrid model that couples the weakly compressible smoothed particle hydrodynamics (SPH) and the quasi-arbitrary Lagrangian-Eulerian finite element method (QALE-FEM) for modelling the wave-structure interaction (WSI) in extreme sea states. The former is a fully Lagrangian mesh-free approach that solves the one-phase incompressible Navier-Stokes model and has shown satisfactory performance in simulating the WSI. The latter is an arbitrary Lagrangian-Eulerian approach based on the fully nonlinear potential theory and can accurately simulate highly nonlinear nonbreaking water waves in a large scale with high computational efficiency. These two models are coupled using a one-way zonal approach, in which the SPH uses a small computational domain near the structure, whereas the QALE-FEM covers the rest of the computational domain and provides wave conditions at the inlet of the SPH domain. The present hybrid model is validated against the experimental results and applied to the CCP-WSI blind test on modelling wave energy converters subjected to extreme focusing waves. The accuracy and convergence of the presented model are discussed.