Hydrodynamics and load shedding behavior of a variable-geometry oscillating surge wave energy converter (OSWEC)

• DOI: 10.1016/j.renene.2022.05.169
• Publication Date: 2022-06-03T03:29:47Z
• Authors: Michael Choiniere; Jacob Davis; Nhu Nguyen; Nathan Tom; Matthew Fowler; Krish Thiagarajan
• Keywords: 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; 7. Clean energy; 01 natural sciences; 0104 chemical sciences

In order to improve their long-term viability, wave energy converters (WEC) need to be able to shed loads when a threshold wave condition is exceeded. As shown by Tom et al. [1], provision of adjustable flaps within the body of an Oscillating Surge Wave Energy Converter (OSWEC) allows wave energy to pass through the device. A control system may then be able to open and close the flaps when waves approaching the device exceed preset thresholds. The variable geometry OSWEC concept studied in this paper is a bottom-hinged rectangular wave paddle with five flaps of elliptical cross-section embedded into the face of the paddle. System ID tests were conducted on this VG-OSWEC device at 1:14 scale in a wave basin. Free decay tests showed that the damping was distinctly nonlinear when the flaps were fully open, and the natural frequency was increased by 40% when compared with the flaps fully closed configuration.