Time-domain analysis of quarter-circle shaped oscillating water column device

Abstract

The present work investigates the working mechanism of the quarter-circle shaped (QCS) OWC-WEC in the time-domain. Several parameters relevant to the functioning of an OWC-WEC are examined for various wave and device parameters. The free surface elevation is presented for a different instant of time to show the functioning of the OWC device in the time domain. The study shows that the OWC-WEC can capture and hold the wave energy for an extended period of time. The resonances appear in the efficiency curve in the longwave zone for higher chamber length and lip wall’s draft. Moreover, the peaks in the efficiency curve occur in the short and moderate wave zones as a result of sloshing effects. The device efficiency becomes higher when the lip wall’s immersion depth is more in the longwave zone. An opposite trend is reported for the moderate and shortwave zone. It is mentioned that the time-domain analysis can simulate the free surface elevation accurately as compared to the frequency domain analysis. In addition, the quarter-circle shaped front wall perform an appreciable role in enhancing the stability of the device.

Keywords

• OWC-WEC
• Boundary element method
• Efficiency
• Wave energy
• Radiation