Mixed Fe-sp Method for Nonlinear Structure-water Interactions with Freak Waves

This paper develops a mixed finite element – smoothing particle method for violent water-structure interactions involving freak waves and separation between structure and water. The structure undergoes a large rigid motion of 6 DOF with a small elastic deformation, so that its elastic displacement relative to the rigid motion can be represented in a mode summation based on FE analysis. The water is assumed inviscid incompressible and its motion governed by nonlinear N-S equation. On the coupling interface where no FS separation happens, the equilibrium and consistence conditions are required. The numerical iteration process is suggested to solve the nonlinear FSI equations, and validation examples are shown a good agreement with available experiment results. GOVERNING EQUATIONS As shown in Fig. 1, a sold in a material domain s  of outside boundary normal vector i  , on which a traction force i T̂ and a displacement