Fully nonlinear time-domain simulation of a backward bent duct buoy floating wave energy converter using an acceleration potential method

Development of wave energy conversion systems may yield many key benefits for society such as the production of electrical power or fresh water for remote communities. However, complex ocean dynamics make it difficult for technology developers to not only address the stability and survivability of their systems, but also to establish energy conversion rates that are fundamental to proving economic viability. Building physical prototypes presents many challenges in terms of cost, accessible facilities, and time requirements. The use of accurate numerical modelling and computer simulation can help guide design and significantly reduce the number of physical prototype tests required and as a result play a primary role in the development of wave energy conversion systems that have to operate in challenging marine environments. SurfPower is an ocean wave energy converter (WEC) that converts wave motion into useful energy through surge and heave motion of a point absorber. The system pumps seawater into a high pressure hydraulic network that generates electricity via a turbine or freshwater via desalination at a facility onshore. The system is nonlinear due to the significant change in draft and mooring reaction load through the energy capture cycle of the device. This makes the use of nonlinear time domain simulation ideal for analysis and design of the system. Furthermore, utilizing a simplified nonlinear hydrodynamic model available in the time domain results in a practical early-stage design tool for system refinement. The focus of this work is to compare the results of scale model testing completed at the Institute for Ocean Technology in St. John’s, Newfoundland, with results produced from an equivalent system simulated in the time domain simulation software ProteusDS. The results give an assessment of the range of error that can be used to assess other experiments of the SurfPower WEC at full scale.

Download Full-text

The underwater resonant airbag: a new wave energy converter

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2017.0192 ◽

2018 ◽

Vol 474 (2215) ◽

pp. 20170192 ◽

Cited By ~ 1

Author(s):

Francis J. M. Farley

Keyword(s):

Wave Energy ◽

Time Domain ◽

Wide Band ◽

Wave Energy Converter ◽

New Wave ◽

Time Domain Simulation ◽

Energy Converter ◽

Flow Through ◽

The Time Domain ◽

Two Peaks

The time-domain simulation follows the heaving of the conical float in waves and calculates the bag shape, ballast motion, adiabatic air pressure and the flow through the turbine. There are two independent oscillators, the float with its resonance and the bag/ballast with its resonance. The coupling of the two oscillators gives rise to a wide band response with two peaks in the capture width each reaching the theoretical λ /2 π . In this new wave energy converter, apart from the turbine, there are no mechanical moving parts, no joints nor pistons, no end stops nor sliding seals, no flaps nor one-way valves. The expected life of the airtight flexible bag remains to be determined, but potential manufacturers are optimistic.

Download Full-text

Performance estimation of resonance-enhanced dual-buoy wave energy converter using coupled time-domain simulation

Renewable Energy ◽

10.1016/j.renene.2020.07.075 ◽

2020 ◽

Vol 160 ◽

pp. 1445-1457 ◽

Cited By ~ 1

Author(s):

Chungkuk Jin ◽

HeonYong Kang ◽

MooHyun Kim ◽

Ilhyoung Cho

Keyword(s):

Wave Energy ◽

Time Domain ◽

Wave Energy Converter ◽

Performance Estimation ◽

Time Domain Simulation ◽

Energy Converter

Download Full-text

Optimization and Time-Domain Simulation of the SEAREV Wave Energy Converter

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 2 ◽

10.1115/omae2005-67286 ◽

2005 ◽

Cited By ~ 17

Author(s):

Aure´lien Babarit ◽

Alain H. Cle´ment ◽

Jean-Christophe Gilloteaux

Keyword(s):

Wave Energy ◽

Time Domain ◽

Mechanical Characteristics ◽

Wave Energy Converter ◽

Floating Body ◽

Time Domain Simulation ◽

Regular Waves ◽

Energy Converter ◽

Working Principle ◽

Latching Control

This paper introduces a new second generation wave energy converter concept named SEAREV [Systeme Electrique Autonome de Recuperation d’Energie des Vagues]. The working principle and linearized equations of the device are described. It is shown how energy absorption depends on the shape of the external floating body and on the mechanical characteristics of the moving mass. This allows to numerically optimize the geometry of the device. Latching control is used to further improve the capture width of the system, with success in regular waves.

Download Full-text