Fully coupled simulation of dynamic characteristics of a backward bent duct buoy oscillating water column wave energy converter

Abstract

In this paper, a fully coupled model for a backward bent duct buoy oscillating water column (BBDB-OWC) wave energy converter (WEC) is established, with the consideration of strong transient nonlinear interactions among ocean waves, BBDB hull motion, mooring system, internal water column oscillation, aerodynamics, turbine rotation and the damping effect of the generator. The model is validated by comparison with experimental results, and then used to investigate the transient characteristics and periodic average performance of the WEC under regular wave conditions. The differences in transient hydrodynamic characteristics and air pressure-flow rate relationship between the fully coupled model and the orifice model are compared. The transient characteristics of an impulse turbine under reciprocating and transient airflows are studied. And the effect of wave period, wave height and load torque coefficient on the average performance of the WEC is investigated.