Hydrodynamic performance of a multi-cylinder LiDAR buoy prototype for wind assessment

To address the technical challenges of difficult construction for traditional wind towers and the susceptibility to resonance of single-column buoys in deep-sea wind resource assessment, this paper proposes a novel distributed multi-column lidar buoy. The hydrodynamic performance of the buoy under typical South China Sea conditions was quantitatively evaluated through 1:5 scale physical model tests, including hydrostatic decay, regular wave, and irregular wave experiments. Key findings are: (1) the multi-column configuration generates 153% additional damping (empirical formula: ζadd = 0.2 (Dg/Dc)−1.5) via interstitial vortex shedding. This shifts the natural periods of sway/surge motion (2.46 s) significantly away from the dominant wave period in the South China Sea (6–8 s), effectively mitigating resonance risk. (2) Compared to a single-column buoy, the multi-column design reduces the roll/pitch angle by 74.4% (from 34.7° to 8.87° under IR10-1 sea state) and the heave displacement by 68.6% (from 15.6 to 4.89 cm). (3) Validation using ANSYS Aqwa numerical simulations yielded errors below 7%. This design offers a highly stable and cost-effective wind measurement platform for deep-sea wind farms.