A SPH-lattice spring method for modelling Fluid Structure Interaction involving composite body and free surface

In this paper, a 3D particle-based Fluid Structure Interaction (FSI) solver based on Smoothed Particle Hydrodynamics (SPH) for fluid modelling and Volume-Compensated Particle Method (VCPM) (or known as Lattice Particle Method) for solid modelling is developed to simulate FSI problems involving composite structure. The 3D FSI method is implemented within the open-source SPH software platform, i.e., DualSPHysics by incorporating the anisotropic composite model with direction-dependent material strength property and laminated composite model consisting of clear material interface(s). In the current work, the force averaging procedure is introduced at the material interface of laminated composite. This technique is then verified using some benchmark solutions for both static and dynamic structural test cases. Next, the FSI solver is verified by solving some 2D/3D FSI benchmark test cases of hydrostatic water column on a composite plate, where theoretical solutions are available. Finally, the capability of the FSI solver in tackling a practical engineering problem involving water slamming on a sandwich hull with presence of large material property discontinuity is demonstrated.