Numerical Simulation of Water Entry of Cylinder Based on Improved Smoothed Particle Hydrodynamics Method

Water entry of structures is a typical hydrodynamic issue in the field of marine engineering. In this paper, an improved Weakly Compressible Smoothed Particle Hydrodynamics (WCSPH) method is utilized to develop a two-dimensional numerical model of water entry of a cylinder in free fall. In order to solve the problem of particle distribution along Lagrangian flow lines inherent to SPH, Gradient Particle Shifting Technique (GPST) is introduced. Besides, a sponge layer is installed at the domain boundary to prevent the effect of boundary reflection pressure. A typical test of water-entry of a tank is conducted. Such results as the surface morphology are compared with reliable experimental data, with a low error. Therefore, the present numerical model is validated. After that, the effect of water-entry velocity on slamming load is discussed. The obtained results shall provide a reference for the further investigation on water-entry impact problems.