3-Dimensional Numerical Analysis of Air Flow inside OWC Type WEC Equipped with Channel of Seawater Exchange and Wave Characteristics around Its Structure (in Case of Irregular Waves)

摘要

Oscillating Water Column (OWC) Wave Energy Converters (WEC) harness electricity through a Power-Take-Off (PTO) system from the induced-airflow by seawater oscillating inside a chamber.In general,an air chamber with a relatively small cross-sectional area is required compared to seawater chamber to obtain high-velocity air in the PTO system,and in order to simulate an accurate air flow rate in the air chamber,a three-dimensional study is required.In this study,the dynamic response of OWC-WEC that is equipped with the channel of seawater exchange for the case of irregular waves has been numerically studied.The open source CFD software,OLAFLOW for the simulation of wave dynamics to the openFOAM and FOAM-extend communities,was used to simulate the interaction between the device and irregular waves.Based on the numerical simulation results,we discussed the fluctuation characteristics of three dimensional air flow in the air-chamber,wave deformation around the structure and the seawater flow inside the channel of seawater exchange.The numerical results the maximum air flow velocity in the air-chamber increases as the Ursell value of the significant wave increases,and the velocity of airflow flowing out from the inside of air chamber to the outside is greater than the speed of flowing into the air chamber from the outside.