Wave simulation using an internal wave-maker in a CIP-based model

A non-reflection internal wave-maker using a momentum source function is coupled with a CIP-based model. The momentum source term derived from the Boussinesq water wave theory equations is employed and added to the Navier-Stokes equations for wave generations. The influence of reflected waves, which is a big problem for a boundary wave maker when containing the interaction of waves and structures, can be avoided by using the internal wave-maker method, because the waves generated by the source function do not interact with reflected waves. A constrained interpolation profile (CIP)-based model is employed to solve the incompressible Navier-Stokes equations with the free surface boundary condition to deal with the water-air-structure interactions. In addition, the VOF-type tangent of hyperbola for interface capturing/slope weighting (THINC/SW) method is used to capture the free surface. The structure is treated by an immersed boundary method. A series of numerical simulations using the momentum source wave-maker are compared with he analytical solution to verify the applicability in a two dimensional numerical wave flume. Furthermore, a more challenging wave decomposition process over a submerged trapezoid breakwater is presented. The numerical results of wave surface profile show a good agreement with the experimental results. It indicates that the CIP-based model with the non-reflection internal wave-maker can provide a more robust modeling of wave generation and wave-structure interaction without being affected by the reflected wave.