Numerical simulation of free-surface waves past semi-submerged two-dimensional rectangular prisms with different aspect ratios and rounding chamfer radii

Free-surface waves past two-dimensional, semi-submerged horizontal rectangular prisms are simulated using OpenFOAM. The effects of prism aspect ratios, rounding chamfer radii, incident wave amplitudes and wavelengths on the hydrodynamic forces on the prism are investigated. The simulations are performed by solving the Navier-Stokes equations without turbulence modelling, and the volume of fluid (VOF) method is employed to capture the interface between water and air. Validation studies are carried out by simulating free-surface waves past a semi-submerged horizontal circular cylinder and a semi-submerged rectangular prism. A good agreement between the present numerical results and the published experimental data in terms of the vertical hydrodynamic force is observed. The present numerical results for the rectangular prisms show that the horizontal hydrodynamic force decreases with increasing rounding chamfer radius, whereas the vertical hydrodynamic force dose not vary significantly with the corner radius over the range from 0.1D to 0.5D (D is the height of the rectangular prism). In addition, both the vertical and horizontal hydrodynamic forces increase with the increase in incident wave amplitude and prism aspect ratio respectively. Finally, the flow mechanism of water particles around the prism is revealed by investigating the velocity magnitude contours with streamlines.