Session: 12-04-01 Blue Economy IV: Modular Marine Platforms: Wave Energy, Aquaculture Integration, and Ocean Sensing

Submission Number: 176197

Power Absorption of Axisymmetric and Asymmetric Float Shapes in Regular and Irregular Waves: an Experimental Investigation With a PTO Damping System 

A comprehensive experimental investigation investigates how variations in float shape affect the hydrodynamic behaviour and power absorption performance of a single-body wave energy converter (WEC). The results and analysis consider the impact of float geometry on key hydrodynamic parameters and the overall efficiency of the device, measured through the PTO system. To ensure a fair comparison between different geometries, near-identical mass and natural frequency conditions were maintained across all tested models. Three float shapes—hemispherical bottom (HB), axisymmetric cone (CH), and asymmetric cylindrical wedge (HW)—were tested under both regular and irregular wave conditions. The PTO system was represented by a linear damper and controller to model different damping scenarios.

The investigation was carried out through a series of well-controlled laboratory experiments to provide reliable and comparable data for each configuration. Special attention was given to maintaining consistent test conditions, ensuring that differences in performance could be attributed solely to changes in float geometry rather than other external factors. Changes in hydrodynamic coefficients caused by variations in float geometry were analysed to determine their influence on the absorbed power and capture width ratio (CWR) of the WEC. The findings indicate that appropriate float design, in combination with suitable damping, can shift device performance from suboptimal to near-optimal conditions, leading to improvement in energy absorption across a range of wave frequencies. These results provide valuable insights into the role of geometry in enhancing WEC efficiency and guide future design optimisation.

Presenting Author: Reza Abbasi The University of Queensland

Presenting Author Biography: I am a PhD researcher in Coastal Engineering at the University of Queensland. My research focuses on the hydrodynamic performance of wave energy converters, with a particular emphasis on the impact of float geometries on energy absorption efficiency. I have extensive experience in both physical and numerical modelling of wave–structure interactions, including experiments conducted in wave tanks and simulations using boundary element methods. My current work investigates strategies to enhance the performance of the M4 wave energy converter through float shape modifications and damping optimization.

Authors:

Reza Abbasi The University of Queensland
Tom E Baldock The University of Queensland