Effect of fish nets hydrodynamics on aero-hydro-servo-elastic aspect of new concept floating wind turbine combine for an offshore aqua culture unit

Over the last few decades, studies found that relying on conventional fossil fuel sources has been giving so many negative impacts to the environment. Depletion of coal along with natural gas and crude oil are also the reasons why we need some new energy alternatives that less harmful and sustainable. Offshore wind energy can be an effective solution due to abundant wind resources and space availability. Unfortunately, the cost of offshore wind energy is expensive. Therefore, an innovative concept of FOWT integrated with an aquaculture is proposed here. This concept is expected to evolve continuously because of the huge profit gained from offshore aquaculture trade. To be qualified, its dynamic behaviour should be evaluated and investigated while considering various environmental conditions. Arafura Sea, which has both fish and wind potential, is chosen as the suitable location for this innovative concept. The environmental conditions, representing different sea state are adopted for the analyses. One incident angle of combined wind, current, and wave loads are being considered in this paper for dominant wind direction. Similarly, a numerical model with dynamic simulation is carried out. Then, the dynamic responses of the FOWT integrated with fish nets, including the periods, motions, tower loads, and mooring tension are numerically examined. While the maximum mooring line tension in the FOWT with fish nets is observed, the expected maximum tension should occur at the mooring line aligned with the direction of the environmental load. Additionally, the highest mooring line tension should occur during operational conditions. This is due to the wind turbine system actively generating electricity during operation, with the rotor facing the incoming wind, resulting in relatively substantial aerodynamic load along with hydrodynamic load. The FOWT with nets motions result shows decreased amplitudes compared with those without nets. This reduction of all the motion amplitudes is the result of the damping effect caused by the presence of nets.