Study of the Interaction between Regular Waves and a Wind-Fish Combined Structure

The combination of a wind turbine and fish cage (wind-fish) is able to solve the complex issue of power supply for deep-sea aquaculture. Nevertheless, the hydrodynamic coupling between the fish cage and the wind turbine foundation is increasingly complex, and there is little research on the related hydrodynamics. In this paper, the hydrodynamic research on the wind turbine foundation and fish cage structure is carried out using numerical simulation, in which the porous medium model is adopted to simulate the effects of the fish cage on the flow field. By analyzing the hydrodynamic characteristics of the combined structure of an offshore wind turbine and aquaculture cage under the action of regular waves, the load on both the cage in the combined structure and the wind turbine foundation, and the overall load on the combined structure of offshore wind turbine and cage are obtained. The effects of wave parameters, structural dimensions, cage submergence depth, and biological attachment on cage load, wind turbine foundation load, and overall load of the combined structure are analyzed. The results demonstrate that the wind turbine foundation is persistently the central part of the combined structure. The wave height, water depth, and degree of attachment of marine organisms all have different effects on the amplitude of the structural load. In contrast, the wave period, cage geometry, and cage submergence depth have no significant effects on the amplitude of the structural load. In addition to the water depth, other factors will affect the proportion of the load on the wind turbine foundation and the total load as well.