Three-dimensional Tidal Dynamic Characteristics and Tidal Current Energy Evaluation in the Southern Sea Area of Hainan Island

Tidal current energy is a kind of marine renewable energy. It has broad application prospects. In this paper, a three-dimensional tidal current numerical model was established, and the model was verified by the measured data of the tide level station. Based on the numerical model, the tidal current feature and tidal current energy distribution were accurately simulated and analyzed in the southern sea area of Hainan Island. The results showed that the annual average velocity of the current was evenly distributed among the space in the study area. But the annual cumulative time of typical velocity in different sea areas was different in space. C2 had more accumulative time for the low-velocity range (<0.4m/s) of the surface, while C1 had more accumulative time for the low-velocity range (<0.3m/s) of the water depth of 8.5m. C3 sea area had more accumulative time in the high-velocity range at the surface (0.4~2.0m/s) and water depth of 8.5m (>0.3m/s). And the area with the highest annual average tidal current energy density at the water depth of 8.5m was C3, which is up to 128.40w/m². C2 sea area had the smallest energy, only 62.63w/m². Compared with C1 and C2 sea areas, the C3 area should be developed emphatically when developing tidal current energy resources in this sea area.