Optimization of tilt suppression and drag reduction for offshore floating photovoltaic floaters

The longitudinal tilt of offshore floating photovoltaic (OFPV) floaters under water flow can disturb the moment equilibrium of the system. This may reduce the reliability and structural integrity of the photovoltaic platform. To analyze the drag characteristics and longitudinal tilt of a typical square OFPV floater, numerical simulation and theoretical analysis were combined in this study. Two optimization methods were considered, including sharp-edge circular-arc profile modification and hemispherical grooves on the bottom surface. The results show that: (1) The sharp-edge circular-arc profile modification reduces the downward suction effect caused by the negative-pressure region beneath the floater. The improved lift-to-drag ratio also makes the moment equilibrium more stable. When this modification is applied to both the upstream and downstream sharp edges, the longitudinal tilt angle is reduced by 28.9% compared with the original case. (2) The hemispherical grooves generate ordered streamwise vortex structures beneath the floater. They suppress the formation and shedding of disordered large-scale vortices, reduce the bottom negative-pressure region, and weaken the downward suction effect. (3) A feedforward neural network (FNN) model was established using key parameters for tilt suppression and drag reduction as inputs. The longitudinal tilt angle was used as the output. A genetic algorithm (GA) was further introduced for global optimization. The optimal design parameters were then determined. These findings can provide a reference for the structural design and stable operation of OFPV floaters.