The Influence Of Buoy Shape On Efficiency Of Oscillating Buoy Wave Energy Converter

Facing to the severe energy and environment situation, people look to the renewable resources, while, most of which it costs too much to take use. And wave energy faces the same problem. Although the technology of Oscillating Water Converter (OWC) is mature and the OWC is very reliable, the efficiency of second conversion of it is very low. Furthermore, it is difficult to reduce the power cost especially in China, where the wave energy density is not high enough. Aiming at making up for the shortcomings of OWC, engineers putd forward the Oscillating Buoy Wave Energy Converter (OBWEC). This paper took the OBWEC as the point cut, researched the influence of the shape of Oscillating Buoy (OB) on the efficiency of OBWEC mainly.The author introduced four of the ocean energies and how to use them. Summarized the advantages and disadvantages of some existing Wave Energy Converters (WEC), gave some information about Fluid and Structure Interaction (FSI) and the best software for FSI——ADINA. Did some meticulous research on the 2D numerical wave tank, set forth the methods of wave making and wave eliminating,especially represented the method of wave making by moving wall. And then with the help of ADINA, this paper discussed the influence of the mesh in the direction of wave propagating and the deep on the quality of wave, besides the time function and time step. The author presented three kind of OBs, and gave the period and damping ratio by numerical method. Discussed the influence factors of the period of four-prism based on the empirical formula. Simulated the motion of OBWEC in the numerical wave tank, compared the efficiency of different shapes of OBs, and analyzed the causes of the result. At last, the author probed into the influence of different equivalent damping of generator. Based on all of the achievements above, the author gave some advices as below when designing the OBWEC:1. Reduce the draft of the OB as far as possible.2. Make the OB have a larger water plane area on the topside, and a smaller one on the lower side. So that it can capture the kinetic energy of wave.3. Design equivalent damping of the generator according to upper bound of the OB-damping.