Similar articles

Abstract: oscillating water column (OWC) devices for wave power extraction are appealing, but are still in need of research. In this study, a series of wave-flume experiments was conducted to examine the hydrodynamic performance of a rectangular OWC device fixed in regular waves. Two types of orifices, slot orifices and circular orifices, were used to simulate the nonlinear power take-off (PTO) mechanism, and the effects of orifice geometry were examined. A two-point measurement method was proposed to reconstruct the instantaneous spatial profile of the water surface inside the OWC chamber for reducing bias in the measured wave power extraction efficiency. The flow characteristics of PTO were described by a quadratic loss coefficient, and our experimental results showed that the quadratic loss coefficient of the slot orifices varied with wave period and slot geometry. Empirical formulas were proposed for the quadratic loss coefficients of the two types of orifices. The ability to determine the quadratic loss coefficient of an orifice will allow us to design orifices for small-scale tests and calculate the power extraction using only pressure measurement. Our results also suggested that the pressure coefficient should be more reliable than the amplification coefficient as an indicator of the power extraction performance of an OWC device.

This paper investigates the hydrodynamic performance of a suspended OWC device fixed in regular waves. A series of wave-flume experiments were conducted. The authors found that the pressure coefficient is more reliable than the amplification coefficient as an indicator to the power extraction performance of an OWC device.

振荡水柱装置波浪水槽试验中用于模拟非线性能量俘获系统的孔口特性

[1]Dai, H.L., Abdelkefi, A., Javed, U., et al., 2015. Modeling and performance of electromagnetic energy harvesting from galloping oscillations. Smart Materials and Structures, 24(4):045012.

[2]Delauré, Y.M.C., Lewis, A., 2003. 3D hydrodynamic modelling of fixed oscillating water column wave power plant by a boundary element methods. Ocean Engineering, 30(3):309-330.

[3]Dizadji, N., Sajadian, S.E., 2011. Modeling and optimization of the chamber of OWC system. Energy, 36(5):2360-2366.

[4]Elhanafi, A., Fleming, A., Macfarlane, G., et al., 2016. Numerical energy balance analysis for an onshore oscillating water column–wave energy converter. Energy, 116:539-557.

[5]Elhanafi, A., Macfarlane, G., Fleming, A., et al., 2017a. Scaling and air compressibility effects on a three-dimensional offshore stationary OWC wave energy converter. Applied Energy, 189:1-20.

[6]Elhanafi, A., Fleming, A., Macfarlane, G., et al., 2017b. Underwater geometrical impact on the hydrodynamic performance of an offshore oscillating water column–wave energy converter. Renewable Energy, 105:209-231.

[7]Esteban, M., Leary, D., 2012. Current developments and future prospects of offshore wind and ocean energy. Applied Energy, 90(1):128-136.

[8]Evans, D.V., 1982. Wave-power absorption by systems of oscillating surface pressure distribution. Journal of Fluid Mechanics, 114:481-499.

[9]Evans, D.V., Porter, R., 1995. Hydrodynamic characteristics of an oscillating water column device. Applied Ocean Research, 17(3):155-164.

[10]Fadaeenejad, M., Shamsipour, R., Rokni, S.D., et al., 2014. New approaches in harnessing wave energy: with special attention to small islands. Renewable and Sustainable Energy Reviews, 29:345-354.

[11]Falcão, A.F.O., 2010. Wave energy utilization: a review of the technologies. Renewable and Sustainable Energy Reviews, 14(3):899-918.

[12]Falcão, A.F.O., Henriques, J.C.C., 2014. Model-prototype similarity of oscillating-water-column wave energy converters. International Journal of Marine Energy, 6:18-34.

[13]Finnemore, E.J., Franzini, J.B., 2002. Fluid Mechanics with Engineering Applications. McGraw-Hill, Boston, USA.

[14]Fossa, M., Guglielmini, G., 2002. Pressure drop and void fraction profiles during horizontal flow through thin and thick orifices. Experimental Thermal and Fluid Science, 26(5):513-523.

[15]Goda, Y., Suzuki, Y., 1976. Estimation of incident and reflected waves in random wave experiments. Proceedings of the 15th International Conference on Coastal Engineering, p.828-845.

[16]Gouaud, F., Rey, V., Piazzola, J., et al., 2010. Experimental study of the hydrodynamic performance of an onshore wave power device in the presence of an underwater mound. Coastal Engineering, 57(11-12):996-1005.

[17]He, F., Huang, Z., 2014. Hydrodynamic performance of pile-supported OWC-type structures as breakwaters: an experimental study. Ocean Engineering, 88:618-626.

[18]He, F., Huang, Z., 2016. Using an oscillating water column structure to reduce wave reflection from a vertical wall. Journal of Waterway, Port, Coastal, and Ocean Engineering, 142(2):04015021.

[19]He, F., Huang, Z., Law, A.W.K., 2012. Hydrodynamic performance of a rectangular floating breakwater with and without pneumatic chambers: an experimental study. Ocean Engineering, 51:16-27.

[20]He, F., Huang, Z., Law, A.W.K., 2013. An experimental study of a floating breakwater with asymmetric pneumatic chambers for wave energy extraction. Applied Energy, 106:222-231.

[21]He, F., Li, M., Huang, Z., 2016. An experimental study of pile-supported OWC-type breakwaters: energy extraction and vortex-induced energy loss. Energies, 9(7):540.

[22]Heath, T.V., 2012. A review of oscillating water columns. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 370(1959):235-245.

[23]Huang, Z., 2007. Wave interaction with one or two rows of closely spaced rectangular cylinders. Ocean Engineering, 34(11-12):1584-1591.

[24]Huang, Z., Li, Y., Liu, Y., 2011. Hydraulic performance and wave loadings of perforated/slotted coastal structures: a review. Ocean Engineering, 38(10):1031-1053.

[25]Iglesias, G., Carballo, R., 2009. Wave energy potential along the Death Coast (Spain). Energy, 34(11):1963-1975.

[26]Iturrioz, A., Guanche, R., Armesto, J.A., et al., 2014. Time-domain modeling of a fixed detached oscillating water column towards a floating multi-chamber device. Ocean Engineering, 76:65-74.

[27]Kuo, Y.S., Lin, C.S., Chung, C.Y., et al., 2015. Wave loading distribution of oscillating water column caisson breakwaters under non-breaking wave forces. Journal of Marine Science and Technology, 23(1):78-87.

[28]Kuo, Y.S., Chung, C.Y., Hsiao, S.C., et al., 2017. Hydrodynamic characteristics of oscillating water column caisson breakwaters. Renewable Energy, 103:439-447.

[29]López, I., Pereiras, B., Castro, F., et al., 2014. Optimisation of turbine-induced damping for an OWC wave energy converter using a RANS-VOF numerical model. Applied Energy, 127:105-114.

[30]Mei, C.C., Liu, P.L., Ippen, A.T., 1974. Quadratic loss and scattering of long waves. Journal of the Waterways, Harbors and Coastal Engineering Division, 100(3):217-239.

[31]Mei, C.C., Stiassnie, M., Yue, D.K.P., 2005. Theory and Applications of Ocean Surface Waves. World Scientific, Singapore.

[32]Morris-Thomas, M.T., Irvin, R.J., Thiagarajan, K.P., 2007. An investigation into the hydrodynamic efficiency of an oscillating water column. Journal of Offshore Mechanics and Arctic Engineering, 129(4):273-278.

[33]Ning, D.Z., Shi, J., Zou, Q.P., et al., 2015. Investigation of hydrodynamic performance of an OWC (oscillating water column) wave energy device using a fully nonlinear HOBEM (higher-order boundary element method). Energy, 83:177-188.

[34]Ning, D.Z., Zhao, X.L., Göteman, M., et al., 2016a. Hydrodynamic performance of a pile-restrained WEC-type floating breakwater: an experimental study. Renewable Energy, 95:531-541.

[35]Ning, D.Z., Wang, R.Q., Gou, Y., et al., 2016b. Numerical and experimental investigation of wave dynamics on a land-fixed OWC device. Energy, 115:326-337.

[36]Rostami, A.B., Armandei, M., 2017. Renewable energy harvesting by vortex-induced motions: review and benchmarking of technologies. Renewable and Sustainable Energy Reviews, 70:193-214.

[37]Sarmento, A.J.N.A., 1992. Wave flume experiments on two-dimensional oscillating water column wave energy devices. Experiments in Fluids, 12(4):286-292.

[38]Sarmento, A.J.N.A., Falcão, A.F.O., 1985. Wave generation by an oscillating surface-pressure and its application in wave-energy extraction. Journal of Fluid Mechanics, 150:467-485.

[39]Sheng, W., Alcorn, R., Lewis, T., 2014. Physical modelling of wave energy converters. Ocean Engineering, 84:29-36.

[40]Stopa, J.E., Cheung, K.F., Chen, Y.L., 2011. Assessment of wave energy resources in Hawaii. Renewable Energy, 36(2):554-567.

[41]Thiruvenkatasamy, K., Neelamani, S., 1997. On the efficiency of wave energy caissons in array. Applied Ocean Research, 19(1):61-72.

[42]Tseng, R.S., Wu, R.H., Huang, C.C., 2000. Model study of a shoreline wave-power system. Ocean Engineering, 27(8):801-821.

[43]Veigas, M., Iglesias, G., 2014. Potentials of a hybrid offshore farm for the island of Fuerteventura. Energy Conversion and Management, 86:300-308.

[44]Vijayakrishna Rapaka, E., Natarajan, R., Neelamani, S., 2004. Experimental investigation on the dynamic response of a moored wave energy device under regular sea waves. Ocean Engineering, 31(5-6):725-743.

[45]Wang, D.J., Katory, M., Li, Y.S., 2002. Analytical and experimental investigation on the hydrodynamic performance of onshore wave-power devices. Ocean Engineering, 29(8):871-885.

[46]Zhang, D., Li, W., Lin, Y., et al., 2012a. An overview of hydraulic systems in wave energy application in China. Renewable and Sustainable Energy Reviews, 16(7):4522-4526.

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

[48]Zheng, S.M., Zhang, Y.H., Zhang, Y.L., et al., 2015. Numerical study on the dynamics of a two-raft wave energy conversion device. Journal of Fluids and Structures, 58:271-290.