Development of a Pivoting Wave Energy Converter Concept
摘要
There is a need for innovative solutions to significantly increase reliability and commercial-viability of wave energy technology to take advantage of the vast wave energy resources available worldwide. Effective designs must demonstrate resilience to harsh conditions while efficiently capturing energy in normal sea states. Initial commercial efforts are likely to focus on near-shore technologies because of their cost advantages, including easier power transmission and maintenance. In this study, an innovative pivoting WEC concept suitable for near-shore uses, which has a survivability mode of operation to mitigate wave-induced structural loads during extreme sea conditions, is proposed. Recent analyses have highlighted the concept’s favourable resonance properties, which enhance power production efficiency during relevant sea states. Numerical and experimental methods were employed to assess the behaviour and wave loads acting on the WEC’s initial design. A potential flow method (time-domain based on diffraction radiation theory) was used to estimate motions and hydrodynamic loading, evaluating second-order wave loads, allowing for comprehensive evaluations across various sea states (of +20 minutes length) at reasonable computational costs. To assess numerical uncertainties, physical testing was conducted using an assembled 1:20 scale physical model. Initial performance assessments, validated by experimental measurements, indicate the capture width ratios of up to 40%, underscoring the concept’s potential. Furthermore, recent survivability tests demonstrated up to 65% decrease of loads on the main moving floater when employing an advanced survivability mode across different critical sea states.