Mario Lopez, Francisco Taveira-Pinto, Paulo Rosa-Santos


This paper deals with the numerical modelling of an innovative technology for harnessing wave energy and its power take-off system. The investigated wave energy converter is CECO, a device based on the principles of oscillating bodies that is being developed at the Faculty of Engineering of the University of Porto, Portugal. The particularity of this concept lies on the relative motion between a floating part and a supporting one, which is restricted to translations along an inclined direction. First, the wave energy converter is modelled in the frequency domain by means of a panel model that is based on the boundary element method. Once obtained the frequency-dependent hydrodynamic coefficients of the floating part, the dynamic equation of motion is solved in the time domain by including, not only the hydrodynamic forces, but also the force of the power take-off system. The results prove the ability of the numerical modelling approach to simulate the behavior of the device and provide insight into its performance.


WEC; oscillating body; numerical model; panel model, Aqwa, capture width.

Full Text:



Ansys. 2016. ANSYS AQWA. 17 ed. ANSYS, Ltd., Canonsburg, PA, USA.

Bosma, B., Sheng, W., and F. Thiebaut. 2014. Performance Assessment of a Floating Power System for the Galway Bay Wave Energy Test Site, Proceedings of the International Conference on Ocean Energy (ICOE), 6 November 2014, Halifax, USA.

Carballo, R., Sánchez, M., Ramos, V., Fraguela, J., and G. Iglesias. 2015. Intra-annual wave resource characterization for energy exploitation: A new decision-aid tool, Energy Conversion and Management; 93, 1-8.

Cummins, W. 1962, The impulse response function and ship motions. The David Taylor Model Basin (DTMB), Washington DC, USA.

Day, A. H., Babarit, A., Fontaine, A., He, Y. P., Kraskowski, M., Murai, M., ... and H.K. Shin. 2015. Hydrodynamic modelling of marine renewable energy devices: A state of the art review, Ocean Engineering, 108, 46-69.

Delauré, Y. M. C., and A. Lewis. 2003. 3D hydrodynamic modelling of fixed oscillating water column wave power plant by a boundary element method. Ocean engineering, 30(3), 309-330.

López, M., Taveira-Pinto, F., and P. Rosa-Santos. 2016. Influence of the power take-off characteristics on the performance of CECO wave energy converter. Energy, 120, 686-697.

López M., Veigas, M., and G. Iglesias. 2015. On the wave energy resource of Peru, Energy Conversion and Management, 90, 34-40.

López, I., Pereiras, B., Castro, F., and G. Iglesias. 2014. Optimisation of turbine-induced damping for an OWC wave energy converter using a RANS-VOF numerical model, Applied Energy; 127, 105-14.

Muliawan, M.J., Karimirad, M., Gao, Z., and T. Moan. 2013. Extreme responses of a combined spar-type floating wind turbine and floating wave energy converter (STC) system with survival modes, Ocean Engineering, 65, 71-82.

Payne, G. S., Taylor, J. R., Bruce, T., and P. Parkin. 2008. Assessment of boundary-element method for modelling a free-floating sloped wave energy device. Part 1: Numerical modelling, Ocean Engineering, 35(3), 333-341.

Rhinefrank, K., Schacher, A., Prudell, J., Hammagren, E., Zhang, Z., Stillinger, C., ... and S. Yim. 2011. Development of a Novel 1: 7 Scale Wave Energy Converter, Proceedings of ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering, ASME, 935-944.

Rosa-Santos, P., Taveira-Pinto, F., Teixeira, L., and J. Ribeiro. 2015. CECO wave energy converter: Experimental proof of concept. Journal of Renewable and Sustainable Energy; 7:061704.

Ruehl, K., and D. Bull. 2012. Wave energy development roadmap: design to commercialization, Oceans, IEE, 1-10.

Taveira-Pinto, F., Iglesias, G., Rosa-Santos, P., and Z.D. Deng. 2015. Preface to Special Topic: Marine Renewable Energy, Journal of Renewable and Sustainable Energy, 7:061601.

Veigas, M., Lopez, M., Romillo, P., Carballo, R., Castro, A., and G. Iglesias. 2015. A proposed wave farm on the Galician coast, Energy Conversion and Management, 99, 102-11.

Veigas, M., López, M., and G. Iglesias. 2014. Assessing the optimal location for a shoreline wave energy converter, Applied Energy, 132, 404-411.

Zhang, Y., Zou, Q. P., and D. Greaves. 2012. Air–water two-phase flow modelling of hydrodynamic performance of an oscillating water column device, Renewable Energy, 41, 159-170.