Numerical Study of Solitary Wave Interaction with a Submerged Semicircular Cylinder

The propagation on submerged structures of solitary wave, as a typical nonlinear wave, has guiding significance for the design and operation of coastal engineering. This paper presents a numerical model based on Navier-Stokes equations to study the interaction of the solitary wave with a submerged semicircular cylinder. A multiphase method is utilized to deal with water and air phase. The model uses the CIP (Constrained Interpolation Profile) method to solve the convection term of the Navier-Stokes equations and the THINC (Tangent of Hyperbola for Interface Capturing) scheme to capture the free surface. Three representative cases different in relative solitary wave height and structure size are simulated and analyzed by this model. By comparing the surface elevations at wave gauges with the experimental data and the documented numerical results, the present model is verified. Then, the wave pressure field around the submerged semicircular cylinder is presented and analyzed. At last, the velocity and vorticity fields are demonstrated to elucidate the characteristics of wave breaking, flow separation, and vortex generation and evolution during the wave-structure interaction. This work presents the fact that this numerical model combining the CIP and THINC methods has the ability to give a comprehensive comprehension of the flow around the structure during the nonlinear interaction of the solitary wave with a submerged structure.