Investigation of the motion response and hydrodynamic performance of a novel moored tidal-powered submerged buoy

AbstractSustained operational viability of marine exploration platforms is significantly constrained by energy supply limitations. A critical emerging technology for achieving energy self-sufficiency involves the utilization of abundant marine energy for in-situ replenishment. This research introduces a novel concept: a single-point moored tidal-powered submerged buoy. This design integrates a horizontal-axis tidal turbine within a conventional moored submerged buoy system to facilitate energy self-sufficiency. This study employed a fully coupled joint simulation numerical model, integrating ANSYS AQWA and ANSYS FLUENT, to investigate the dynamic characteristics and hydrodynamic performance of the mooring system. Subsequently, under a range of operating conditions, the mooring motion characteristics of the device throughout the downstream drifting process are analyzed, and the influence of the mooring-induced motions on the hydrodynamic performance of the turbine is investigated. The research findings indicate that the implementation of tidal turbines induces offset and downward movement in the mooring system, with the extent of these excursions correlating positively with inflow velocity and mooring line length. Furthermore, while the power and thrust coefficients of the turbine are slightly reduced in the moored configuration compared to the fixed-axis configuration, the maximum power coefficient of 0.344 demonstrates the feasibility of this approach.