A sph model with open relaxation boundary for wave generation and absorption

Abstract

In this paper, a numerical wave tank with open relaxation boundary for wave simulation is presented under the framework of weakly compressible Smoothed Particle Hydrodynamics (SPH). The open relaxation boundary consists of open boundaries and relaxation particles. A relaxation function is applied for the relaxation particles which are placed between the inflow/outflow zone and the fluid domain. Open particles lie in the inflow/outflow regions to avoid kernel truncation. The open particles and relaxation particles can be created and deleted depending on the fluid motion around the open boundaries, and the properties of these particles can be obtained from theoretical resolution or by extrapolating within the domain. The model is validated by simulating a 2nd Stokes wave and wave runup on a beach. The results demonstrate that the present SPH model with open relaxation boundary works well in wave generation and absorption.