Abstract: A floating type Backward-Bent Duct Buoy (BBDB) is a wave energy conversion device with an Oscillating Water Column (OWC) at the front side. The device captures the wave energy using the heaving, the pitching, the surging motion of BBDB and the heaving motion of OWC, and generates the oscillating air flow to drive the turbine-generator.
The system introduces a special impulse turbine which can rotate unidirectionally and the turbine has advantage for the complete self-starting. An eigenfunction expansion method is introduced for analyzing the BBDB with OWC. It is confirmed that these solutions give good agreement with several experimental results. It is shown in a design method how to make BBDB match the turbine characteristics. The BBDB size and the turbine diameter are determined by considering the cost corresponding to the smallest size under the same output.
