Dynamic responses of a floating tidal turbine with 6-DOF prescribed floater motions. (1st October 2018)

• Record Type: Journal Article
• Authors: Guo, Xiaoxian; Yang, Jianmin; Lu, Wenyue; Li, Xin
• Is Part Of: Ocean engineering. Volume 165(2018)
• Page Start: 426
• Page End: 437
• Publication Date: 2018-10-01
• Subjects: Floating tidal turbine -- Dynamic response -- Blade element momentum -- Linear surface wave -- Wave induced load; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2018.07.017
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: This study aims to reveal the dynamic response and power output characteristics of a floating tidal turbine with prescribed motions in six degrees of freedom. Floater motions were calculated in the time domain based on linear potential theory. Both wave-induced inflow fields and floater motions are considered in a modified blade element momentum theory model for rotor load simulation. Generator power production and loads on a reference tidal turbine system were investigated. The torque and thrust response spectra are found to be dominated by floater-motion-induced contributions, and two response peaks can be clearly identified. A cancellation effect occurs between direct wave effects and floater-motion-induced loads, and horizontal and vertical rotor positions can significantly affect the dynamic responses of the blade loads; the rotor should be placed close to the floater centre to avoid large floater-motion-induced velocity on the blade section. Sensitivity studies are carried out with varying significant wave heights and peak periods. These results may contribute to a general understanding of floater-induced dynamic loads on floating tidal turbines in a random sea. Highlights: The combined wave and platform motion effects on the load characteristics of a floating tidal turbine are investigated. The most significant response appears to be due to surge and pitch motion of the floater not the direct wave effects. A cancellation effect between direct wave and floater-motion-induced loads occurs. Strong sensitivity is shown for the location of the rotor due to the impact of surge and pitch motion.