Numerical Simulation On The Investigation Of Hydrodynamic Characteristics Of Artificial Reef In Waves

In recent years, with the global fishery resources declining and people’s awareness of marine environmental protection increasing, restoration and protection of the offshore fishery resources has increasingly become the focus of attention. An important measure in every country’s work of protecting and profiling fishery resources and repairing the marine environment is to build the marine ranch. Artificial reefs, which are manmade structures to mimic some characteristics of natural reefs, are placed on the seabed when building the marine ranch. They can protect and increase the fishery resources, and also can reduce coastal erosion. Artificial reefs will be affected by both waves and currents when placed on the seabed, and they will also have an impact on distribution of flow field around. Artificial reefs achieve its ecological functions by the effect of flow field it brings. And artificial reefs’ physical stability under the action of waves and currents is the assurance of its long-term ecological function. Therefore, it is extremely essential to investigate the hydrodynamic characteristics of submerged artificial reefs in waves.Currently the study of artificial reefs mainly focus on its ecological effect and the distribution of flow field around it under the action of currents, while the investigations of hydrodynamic characteristics of submerged artificial reef in waves are relatively few. In this article, the computational fluid dynamics software FLUENT was used to carry out numerical simulation. Based on the finite volume method, adopting the movement border as a wave generator, a 3D-numerical wave tank was established by the volume of fluid (VOF) method which was used to simulate the interaction between artificial reef and waves. Based on this numerical model, the force of the hollow triangular artificial reef under the action of waves was investigated. Through comparing the numerical results with the physical model experiment results, the accuracy of the simulation of waves and forces was verified. According to the results of numerical simulation, the qualitative analysis of the distribution of the flow field around the triangular artificial reef was made. The hydrodynamic coefficients of the single triangular artificial reef in wave were fitted out by analyzing the data. The simulation results also show that a strong upward flow and reflow appear around the artificial reef, and vortices appear in the internal structure. The investigation results provide a theoretical basis for the design and optimization of artificial reef. The main content of this article includes five parts. The first chapter gives an exhibition on the background of the subject and the aim of the study, and the development tendency of the research is also referred. The second chapter is about the basic theory and the numerical model, including the governing equations, numerical methods and the establishment of the three-dimensional numerical wave flume. We also verified the effectiveness of making wave and reducing wave. In the third chapter, we used the established numerical wave flume to simulate the wave action on the single triangular artificial reef. Through comparison with physical model test results, we preliminarily investigated the hydrodynamic characteristics of the single triangular artificial reef in waves. In the fourth chapter, we investigated the hydrodynamic characteristics of combined triangular artificial reefs in waves. In the last chapter, we made a calculation on the physical stability of the triangular artificial reef in waves.