Hydrodynamic response and structural analysis of a star-type floating photovoltaic system during towing operations

With the growing global demand for renewable energy, and floating offshore photovoltaic (FOPV) systems have garnered increasing development potential. To address the challenges of towing construction for FOPV systems in complex marine environments and to explore pathways for large-scale application, this paper proposes a coupled hydrodynamic-structural analysis method for the star-type floating photovoltaic structure. By integrating numerical simulations and physical experiments, it systematically investigates the hydrodynamic response, structural reliability, and operational safety boundaries during towing operations. The results indicate that the star-type structure exhibits excellent stability under complex sea conditions, demonstrating a high degree of consistency between its motion response and the numerical simulation results, with an error rate of <9.38 %. It is recommended that towing operations be conducted under level 3 sea states to avoid wave overtopping; the heave motion reaches 1.77 meters under level 4 sea states, while the maximum pitch angle is 8.15° under level 5 sea states. The motion response is highly sensitive to the peak period. Structural stress is significantly affected by the coupling of towing speed and sea states, with wave forces dominating the stress under different sea conditions. At a towing speed of 4 knots, as sea state levels 1–4 increase, the average stress of the floating body increases by 11.09 %. This study comprehensively evaluates the stability and reliability of the FOPV system under complex marine conditions, providing theoretical support for formulating towing schemes and risk assessments for FOPV deployments.