A hydroelastic fluid-structure interaction solver based on a coupled 3D SPH-FEM method

The present work is aimed at developing an accurate numerical self-programming framework to simulate the violent 3D fluid-structure interaction process by a coupled Lagrangian particle method and mesh-based method, where the hydrodynamic load is solved by smoothed particle hydrodynamics (SPH) and the structural dynamics is predicted by the Finite Element method (FEM). It should be noted that the degenerated continuum theory is introduced to describe the structure dynamics, which can be easily applied to the complex structure discretization in some cases. And at the same time, a normal flux approach is developed to overcome the shortcoming of support domain truncation for fluid particles near the fluid-structure interface. Additionally, some other advanced numerical processing techniques are employed to improve the coupling stability and robustness of the 3D SPH-FEM solver, such as the δ-SPH model and the conventional sequential staggered algorithm. Finally, through several typical hydro-elastic benchmark tests and commercial software tests, including the hydrostatic water column test, free surface flow-structure interaction and elastic structure water entry slamming test, the numerical accuracy and overall stability are discussed and verified systematically, which can promote the numerical algorithm research on hydro-elastic effect in ocean engineering.