Nonlinear simulations of wave-induced motions of a freely floating body using WCSPH method

•A WCSPH model is improved to simulate wave interaction with floating bodies.•The interface boundaries are modeled by an improved algorithm based on DBPs.•The force on boundaries is evaluated using volume integration of stress tensors.•Motions of the floating bodies are numerically and experimentally quantified.

Nonlinear interactions between waves and floating bodies are investigated using the weakly compressible Smoothed Particle Hydrodynamic (WCSPH) method. An improved algorithm based on the dynamic boundary particles (DBPs) is proposed to treat the moving boundary of the floating body. The force exerted on the floating body boundary particle by the particles surrounding it is evaluated using the volume integration of the stress tensors obtained from the momentum equation in its compact support. The improved WCSPH model is validated by the experimental results. The numerical test cases of the vertical oscillation of a rectangular box, the damped rolling oscillation of a floating box and the wave forces on a fixed rectangular box are then carried out to demonstrate the performance of the proposed model. Finally the evolution in time of the dynamic response of the freely floating body under nonlinear waves are discussed and compared with experimental results.