Preliminary study for development of marine hydropower system using Tidal Jet Generator

To prevent the harmful effect of global warming, development of renewable energy source comes into the spotlight. In these days, the nations, which are located in near shore like South Korea and some European nations, have been developing renewable energy systems from ocean energy. However, to develop the Ocean energy, it spends too much expenses. For example, over the 4 billion dollar was spent for the construction of the Sihwa tidal power station. And it causes some environmental problems. In this study, preliminary study for the development of marine hydropower was conducted. The marine hydropower system proposed in this study is utilizing the Tidal Jet Generator (TJG) for generating electricity. During both phases of tide, strong and uni-directional jets can be obtained locally from the inlet of the TJG, due to the water level difference between the inner and outer sides of TJG. Therefore we supposed that tidal jet can be harnessed as the renewable energy source. To conduct this study, theoretical equation based on Torricelli equilibrium was used for calculating the maximum velocity from TJG. From the result, the duration time for generating TJG was too short to apply for renewable energy source. We supposed that Torricelli equilibrium ignores the viscous force. Thus computational fluid dynamics (CFD) was applied to calculating the velocity and duration time. CFD results which considered the viscous force and shape of outlet represents that CFD result is different from theoretical result. And CFD results will be compared with the experimental result. The hydraulic experiment will be performed based on model size.