Numerical Simulation of the Hydrodynamic Characteristics of the Porous I-type Composite Breakwater

Based on the three-dimensional Reynolds-averaged Navier-Stokes equation with the closure of renormalization group k-epsilon turbulence model and volume of fluid method, a wave-breakwater interaction numerical flume was developed to examine the wave-structure interaction of the porous I-type composite (PITC) breakwater. The transmission and reflection coefficients of the breakwater at different wave steepness H/L are quantitatively analyzed, and the wave-dissipating performance of the breakwater is compared. By changing the submerged depth of the breakwater, the velocity field, and vorticity field in the wave propagation process are analyzed, and the optimal working water depth of the new breakwater is explored. The results show that the vertical wave force on the PITC breakwater is greater than the horizontal wave force. In addition, during the wave dissipation process, the transverse baffle provided by the new breakwater destroys the trajectory of the water particle. In the interior of the wave-breaking chamber, the water that enters from the gap of the permeable plate mixes with the water entering through the bottom hole. The turbulence created by this process further dissipates the wave energy. The relative submergence depth of h/d has a great influence on the hydrodynamic characteristics. When the relative depth is large, most of the wave energy enters the breakwater, the wave energy dissipation of the breakwater is large, and the wave-absorbing effect is good. These research results provide important referential data for the study of permeable plate breakwaters.