Numerical Research Of Irregular Waves Acting On Perforated Caisson

In recent years,with the development and improvement of modern ocean engineering technology.Traditional solid wall breakwater structrue has been unable to meet various needs of practical engineering,so it is highly important for us to propose new types of breakwater structure.Since perforated caisson breakwater was put forward,it has been widely used in practical coastal engineering,because it can effectively reduce the wave reflection,improve the structural force and provide convenience for construction.Many researchers have carried on the detailed research on the hydrodynamic characteristics of the perforated caisson structure,and most of the research results are mainly based on the physical model test,but the researches based on the numerical simulation,especially the irregular wave results are rare.Based on the Navier-Stokes equation and the three-step finite element method,the CLEAR-VOF method is also used to track the free surface of the fluid.The turbulence effect in the fluid is simulated by the method of large eddy simulation,and the secondary reflection wave is eliminated by the active absorption method.The simulation of the irregular wave adopts the JONSWAP spectrum,and the spectral interval was divided by the equal energy method.The two-dimensional irregular wave numerical water tank was established,and the propagation of the irregular wave in the tank was successfully simulated.On this basis,this dissertation numerically simulates the irregular wave acting on the perforated caisson,and calculates the reflection coefficient and total wave force of caisson structure.And the simulation results were campared with the results of physical model test,numerical simulation results of other scholars and industry norms.The cmparison results are in good agreement with other results,which verifies the validity and reliability of the numerical model proposed in this paper;The influence of the relative wave chamber width,relative water depth,relative wave height and opening ratio of perforated plate on the reflection coefficient and force of the perforated caisson were analyzed.The research results provide a reference for the practical engineering application and design of the perforated caisson type breakwater.