Experimental study on the wave energy capture performance of a dual-chamber oscillating water column wave energy converter

This study investigates the wave energy capture performance of a dual-chamber oscillating water column (OWC) wave energy converter (WEC) through experiments. The effects of PTO (Power Take-Off) damping, opening size, and incident wave condition on efficiency of the device are examined. The results indicate that reducing the opening size limits the penetration of wave energy into the device while restricting the flow of external seawater into and out of the device's chambers. This reduction causes a decrease in the efficiency of both chambers, although the interaction between the two chambers is enhanced. The study also reveals that higher wave heights result in an increase in pneumatic power that is insufficient to offset the increase in the incident wave energy density, leading to a decrease in the capture width ratio (CWR) of the device. Compared to regular wave experiments, the peak energy conversion efficiency of the device decreases under irregular wave conditions, but the effective energy capture bandwidth slightly widens. Furthermore, the study finds that the device's energy capture performance is superior when the chamber openings face the incoming waves. These findings contribute to the structural optimization and performance enhancement of dual-chamber OWC WECs.