Bergillos Rafael J, Rodriguez-Delgado Cristobal, Allen James, Iglesias Gregorio
Hydraulic Engineering Area, Department of Agronomy, University of Córdoba, Rabanales Campus, Leonardo Da Vinci Building, Córdoba 14071, Spain.
School of Engineering, University of Plymouth, Plymouth PL4 8AA, UK; PROES Consultores, Calle San Germán 39, Madrid 28020, Spain.
Sci Total Environ. 2019 Jun 10;668:1232-1241. doi: 10.1016/j.scitotenv.2019.03.022. Epub 2019 Mar 6.
Wave farms, i.e., arrays of wave energy converters (WECs), have been proposed to fulfil the dual function of carbon-free energy generation and coastal protection. The objective of this work is to investigate, for the first time, how the coastal protection performance against flooding is affected by WEC geometry. This is done by means of a case study with WaveCat WECs (floating, overtopping WECs) deployed off the Playa Granada beach (Spain). To this end, two models of WaveCat WECs with different geometries are tested in a laboratory tank at a 1:30 scale under low-, mid- and high-energy sea states representative of the wave conditions of Playa Granada. The geometries differed in the angle between the twin hulls (wedge angle) of WaveCat: 30° and 60°. The reflection and transmission coefficients thus obtained are used in a coupled numerical modelling approach, combining wave and coastal processes models (SWAN and XBeach-G, respectively). We find that WECs with an angle of 60° provide more (less) protection for long (short) wave periods in terms of reductions in wave height and run-up on the beach. As for the flooded dry beach areas, they are generally smaller for WECs with 60°, with only some exceptions under mild conditions. Thus, considering that beach inundation usually occurs under high-energy, storm conditions, we conclude that the wave farm composed by WECs with a wedge angle of 60° is more efficient against coastal flooding.
波浪农场，即波浪能量转换器（WEC）阵列，已被提议用于实现无碳能源生产和海岸保护的双重功能。这项工作的目的是首次研究WEC的几何形状如何影响其防洪海岸保护性能。这是通过一个案例研究来完成的，该研究在西班牙普拉亚格拉纳达海滩外部署了WaveCat WEC（浮动式、越浪式WEC）。为此，在实验室水槽中以1:30的比例对两种不同几何形状的WaveCat WEC模型进行了测试，测试环境为代表普拉亚格拉纳达波浪条件的低、中、高能海况。WaveCat双体船之间的夹角（楔角）不同，分别为30°和60°。由此获得的反射和透射系数被用于一种耦合数值建模方法中，该方法结合了波浪模型和海岸过程模型（分别为SWAN和XBeach-G）。我们发现，从降低波高和海滩上的爬高方面来看，楔角为60°的WEC在长（短）波周期下能提供更多（更少）的保护。至于被淹没的干滩区域，楔角为60°的WEC通常较小，在温和条件下只有一些例外情况。因此，考虑到海滩淹没通常发生在高能风暴条件下，我们得出结论，由楔角为60°的WEC组成的波浪农场在抵御海岸洪水方面更有效。
