Research on wave energy harvesting and dissipation for buoys based on Savonius rotors

Compared to traditional deep-sea cages, ship-type net cages offer advantages such as self-adjusting orientation and reduced wave-facing area. However, they still face challenges like the need to enhance wave attenuation and flow reduction capabilities at the bow section and difficulties in meeting power demands. The Savonius rotor (S-rotor) shows application potential in marine energy utilization due to its simple structure and good self-starting performance. This paper proposes integrating the S-rotor with the net cage pontoon framework to enhance the wave resistance and power generation capacity. Three configurations of S-rotor dual-pontoon integrated mechanisms are proposed: external rotor, embedded rotor, and hybrid distributed rotor. Through combined numerical simulation and physical experiments, a comparative analysis of the coupled hydrodynamic performance of these integrated mechanisms was conducted, revealing that the hybrid distributed configuration shows significant advantages in comprehensive wave energy utilization. Furthermore, the Analytic Hierarchy Process (AHP) was innovatively introduced to establish a four-dimensional decision-making model. A dynamic decision system was constructed with wave attenuation performance and power generation efficiency as core indicators, confirming that the hybrid configuration stably leads in comprehensive score within a weight fluctuation range of ±20 %, providing a generalizable methodological tool for multi-objective optimization of marine composite structures.