Numerical analysis of an onshore oscillating water column wave energy converter for different wall slopes
Keywords:
oscillating water column; wave energy; renewable energy; numerical simulationAbstract
An alternative to the energy matrix expansion, due to the increase of global electricity demand, is the renewable sea wave energy source, which has high energy potential. The Oscillating Water Column (OWC) converter is one of the most studied, although it is not yet used at commercial scale. Therefore, searching the optimal geometric configuration is fundamental to turn this device viable. This study proposes a numerical analysis of an onshore OWC device for different slopes of chamber walls (from 40o to 90o) and equipped with a Wells turbine. Simulations are performed by means of the FLUENT® software, based on Reynolds-averaged Navier-Stokes (RANS) equations for an incompressible 2D flow, the k-É› turbulence model and the Volume of Fluid (VOF) method. Analyses of the behavior of run up/down in the front wall, sloshing inside the chamber and the energy balance of the OWC are carried out for incident waves with periods from 6 to 12 s and height of 1.5 m. Chamber with wall slopes of 40o reaches the highest extracted energy EE at wave periods of 9 and 10.5s (70% of the incident wave energy) and higher run-up/down on the front wall and sloshing inside the chamber. However, chamber with wall slopes of 90o has more regularity of EE at the range of wave periods, which allows concluding that the choice of the optimal chamber wall slope depends mainly on the sea state characteristics.
References
Conde, J.M.P.; Teixeira, P.R.F.; Didier, E. Numerical simulation of an oscillating water column wave energy
converter: comparison of two numerical code. In: Proceedings of the 21th International Offshore and Polar
Engineering Conference, Maui, 2011; pp. 688-674.
Costa, R.S.; Lima, F.J.L.D.; Rüther, R.; Abreu, S.L.D.; Tiepolo, G.M.; Pereira, S.V.; Souza, J.G.D. Atlas Brasileiro de
Energia Solar, 2ª ed.: INPE. São José dos Campos ”“ SP, 2017 (in Portuguese).
Dean, R.G.; Dalrymple, R.A. Water wave mechanics for engineers and scientists. First Published in 1984 by
Prentice Hall, Inc. World scientific publishing Co. Pte. Ltd., London, 2000.
Dias, J.; Mendonça, A.; Didier, E.; Neves, M.G.; Conde, J.M.P.; Teixeira, P.R.F. Application of URANS-VOF models
in hydrodynamics study of oscillating water column. In: Proceedings of SCACR2015 - International Short
Course/Conference on Applied Coastal Research, Florence, Italy, 2015.
Didier, E.; Teixeira, P.R.F.; Neves, M.G. A 3D Numerical Wave Tank for Coastal Engineering Studies. Defect and
diffusion forum: 2016, volume 372, pp. 1-10.
Elhanafi, A.; Fleming, A.; Macfarlane, G.; Leong, Z. Numerical energy balance analysis for an onshore oscillating
water column wave energy converter. Enegry 2016, volume 116, pp. 539-557.
Falcão, A.F. Control of an oscillating-water-column wave power plant for maximum energy production. Applied
Ocean Research 2002, volume 24, n. 2, pp. 73-82.
FLUENT, 2016. User’s Guide. ANSYS Inc.
Folley, M.; Whittaker, T. Identification of non-linear flow characteristics of the LIMPET shoreline OWC. In.
Proceedings of The Twelfth International Offshore and Polar Engineering Conference. Kitakyushu, Japan, 2002.
Gaspar, A.L.; Teixeira, P.R.F.; Didier, E. Numerical analysis of the performance of two onshore oscillating water
column wave energy converters at different chamber wall slopes. Ocean Eng. 2020, volume 201, Nº107119.
IEA (International Energy Agency) Key World Energy Statistics 2020. Available in :<
http://energyatlas.iea.org/#!/tellmap/-1118783123> Access in Dec. 2020.
Lagoun, M.S.; Benalia, A.; Benbouzid, M.E.H. Ocean Wave Converters: State of the Art and Current Status. In
Proceedings of International Energy Conference, IEEE 2010. Manama, Bahrain, 2010, pp. 636-641.
Conde, J.M.P.; Teixeira, P.R.F.; Didier, E. Numerical simulation of an oscillating water column wave energy
converter: comparison of two numerical code. In: Proceedings of the 21th International Offshore and Polar
Engineering Conference, Maui, 2011; pp. 688-674.
Costa, R.S.; Lima, F.J.L.D.; Rüther, R.; Abreu, S.L.D.; Tiepolo, G.M.; Pereira, S.V.; Souza, J.G.D. Atlas Brasileiro de
Energia Solar, 2ª ed.: INPE. São José dos Campos ”“ SP, 2017 (in Portuguese).
Dean, R.G.; Dalrymple, R.A. Water wave mechanics for engineers and scientists. First Published in 1984 by
Prentice Hall, Inc. World scientific publishing Co. Pte. Ltd., London, 2000.
Dias, J.; Mendonça, A.; Didier, E.; Neves, M.G.; Conde, J.M.P.; Teixeira, P.R.F. Application of URANS-VOF models
in hydrodynamics study of oscillating water column. In: Proceedings of SCACR2015 - International Short
Course/Conference on Applied Coastal Research, Florence, Italy, 2015.
Didier, E.; Teixeira, P.R.F.; Neves, M.G. A 3D Numerical Wave Tank for Coastal Engineering Studies. Defect and
diffusion forum: 2016, volume 372, pp. 1-10.
Elhanafi, A.; Fleming, A.; Macfarlane, G.; Leong, Z. Numerical energy balance analysis for an onshore oscillating
water column wave energy converter. Enegry 2016, volume 116, pp. 539-557.
Falcão, A.F. Control of an oscillating-water-column wave power plant for maximum energy production. Applied
Ocean Research 2002, volume 24, n. 2, pp. 73-82.
FLUENT, 2016. User’s Guide. ANSYS Inc.
Folley, M.; Whittaker, T. Identification of non-linear flow characteristics of the LIMPET shoreline OWC. In.
Proceedings of The Twelfth International Offshore and Polar Engineering Conference. Kitakyushu, Japan, 2002.
Gaspar, A.L.; Teixeira, P.R.F.; Didier, E. Numerical analysis of the performance of two onshore oscillating water
column wave energy converters at different chamber wall slopes. Ocean Eng. 2020, volume 201, Nº107119.
IEA (International Energy Agency) Key World Energy Statistics 2020. Available in :<
http://energyatlas.iea.org/#!/tellmap/-1118783123> Access in Dec. 2020.
Lagoun, M.S.; Benalia, A.; Benbouzid, M.E.H. Ocean Wave Converters: State of the Art and Current Status. In
Proceedings of International Energy Conference, IEEE 2010. Manama, Bahrain, 2010, pp. 636-641.
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