Development of three-dimensional numerical wave basin for simulation of extreme events in ocea

A three-dimensional numerical wave basin is established, in which different types of directional waves can be generated and the offshore structures can be tested. A fully nonlinear potential flow model is employed to incorporate the nonlinear properties of the waves and the higher-order boundary element method (HOBEM) is adopted to solve the mixed boundary value problem. The developed numerical model is validated with the experiments of the focused waves carried out in the physical wave tank at the Hydraulic Engineering Laboratory of National University of Singapore. It is found that the water depth has significant effect on the nonlinearity of the focused waves and the wave steepness can magnify the water depth effect. To consider the directionality of the wave propagation, the present model is further developed to be capable of generating directional oblique waves and focused waves. An active wave absorption scheme is adopted to avoid the wave reflections. It is also proved to simulate the interactions between different types of directional waves and bodies. The present model provides a good platform for the future development of the numerical wave basin capable of hosting more complicated cases in Offshore Engineering.