Array scaling effects on hydrodynamic loading, connector force distribution and mooring response in rope-mesh floating photovoltaic system

Floating photovoltaic (FPV) systems offer a promising route for expanding solar generation in coastal and offshore water bodies. As arrays grow to larger multi-floater configurations, the wave-induced motions, inter-module connector forces, and mooring loads become complex. This study presents high-fidelity CFD simulations of 3×3 and 4×4 rope-mesh FPV arrays subjected to regular wave loading. Each module was modelled as an independent six-degree-of-freedom rigid body with elastic ​spring connectors and a mooring system, enabling insights into floater motions, connector forces, and mooring loads at the individual panel level across 16 wave conditions. The RAO heave exhibited front-to-rear attenuation driven by wave sheltering, with the front row heave increasing and the rear row heave decreasing at shorter relative wavelengths, progressively increasing the range of motion contrast observed across the array. Pitch amplification was observed in the 4×4 array at λ/L ≈ 1.43 and H/h = 2.14. In the 3×3 array, the highest streamwise connector forces occur between the middle and rear floaters, whereas in the 4×4 array, they shift to the connectors between the interior unmoored floater rows, indicating that the critical load-bearing connector location moves from the array boundary toward the interior as the array grows. Fast Fourier Transform (FFT) decomposition of the mooring force time histories showed a significant second-harmonic contribution, with F₂/F₁ ratios of 0.29–0.81 across all tested conditions, indicating that mooring systems designed solely on peak tension could progressively underestimate the secondary loading and fatigue as FPV arrays scale to larger configurations.