Numerical study of wave effect on water entry of a three-dimensional symmetric wedge

Marine and aerospace structures are frequently subject to impact loads on wave surface. The primary aim of this paper is to obtain a fundamental understanding of wave effect on wedge entry problem. A three-dimensional (3D) full-scale symmetric wedge with three degrees of freedom (3DOF) is numerically modeled in the incompressible air-water two phase flows. The numerical implementation and regular wave surface are realized in Reynolds-averaged Navier-Stokes equations (RANS) framework (STAR-CCM+ 2020.1) by combining with volume of fluid (VOF) and velocity-inlet wavemaking methods. The accuracy of the present numerical model is validated by the experimental tests. Various case studies are then carried out to investigate the difference between calm water and wave crest entries, and to analyze the mechanisms of the wave position and wave height effects through several physical results, including acceleration, velocity, pressure, displacement, rotation and free surface. Results indicate that the process of water entry can be divided into early, vertical-down and bounce-up stages. Further, the wave effect on the water entry problem can be explained as that the incident wave particle velocities and the surface slope result in the variations of effective impacting velocity and entry type of the wedge, and thus remarkably influence the hydrodynamic loads and rotating motion of the wedge. The parametric study reveals that the wave height has no significant effect on the vertical force but positively affects the horizontal impact force and rotating motion of the wedge.