Numerical simulation of tidal current around Keelung Sill off Northern Taiwan

Tidal power is a renewable energy source and considered as one of energy solutions in the context of global warming. The Keelung Sill is a seamount-like formation with depths in the range of 10-40m on a 60m deep sea floor. It is located between the Keelung Island and the Keelung Harbor on the north coast of Taiwan. Due to its shallowness, currents measured at the Sill are often above 1.5 m/s and can be as high as 2.5 m/s. Since Keelung Sill is only about 3 km off the Keelung Harbor, it can be an ideal site for tidal power generation. In this study we have established a two-dimensional numerical model to simulate tidal currents around the Keelung Sill. The numerical model to be used is based on the hydrodynamic equations and constructed by the finite difference method. The model was mainly driven by tides from open boundaries, in which the tides are obtained from a global tidal model of Japan´s National Astronomical Observatory (NAO). The model result indicated that the strongest current in a 24-hr cycle is about 1.0 m/s, which is lower than observed. It may be due to the lunar phase of simulation day different from the measurement time.