Analytical investigation on the hydrodynamic performance of a multi-pontoon breakwater-WEC system. (15th January 2021)

• Record Type: Journal Article
• Authors: Zhao, Xuanlie; Xue, Rong; Geng, Jing; Göteman, Malin
• Is Part Of: Ocean engineering. Volume 220(2021)
• Publication Date: 2021-01-15
• Subjects: Wave energy converters -- Multi-pontoon system -- Floating breakwaters -- Analytical model -- Effective frequency bandwidth; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2020.108394
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: Based on linear potential flow theory and the matching eigenfunction expansion method, an analytical model is developed to investigate the hydrodynamics of two-dimensional multi-pontoon floating breakwaters that also work as oscillating buoy wave energy converters. The pontoons are constrained to independent heave motion and the linear power take-off damping is used to calculate the absorbed power. The proposed model is verified using the principle of energy conservation. Performance of the system with different numbers of pontoons is studied, and the results show that the wave attenuation performanceper, the energy capture performance, and the effective frequency bandwidth are superior in the multi-pontoon system as compared to the single-pontoon systems with the same volume. Bragg resonance dominates the wave energy extraction performance at certain frequencies, which reduces the hydrodynamic efficiency. Conversely, in the frequency region away from Bragg resonance, the hydrodynamic efficiency is enhanced due to the constructive hydrodynamic interactions of the multi-body system. Highlights: A floating breakwater with integrated multiple wave energy converters is studied analytically. The effective frequency bandwidth of the multi-pontoon system is superior to that of the single-pontoon system. The wave energy extraction performance of the multi-pontoon system is reduced by Bragg reflection.