Development of an SPH-based numerical wave–current tank and application to wave energy converters
Salvatore Capasso, Bonaventura Tagliafierro, Iván Martínez-Estévez, Corrado Altomare, M. Gómez‐Gesteira, Malin Göteman, Giacomo Viccione
Abstract
This research proposes a high-fidelity based numerical tank designed to analyze the modified hydrodynamics that develops in waves–current fields, aimed at generating power matrices for wave energy converters (WEC). This tank is developed within the open source DualSPHysics Lagrangian framework using the Smoothed Particle Hydrodynamics (SPH) method, validated with physical data, and applied to simulate a point-absorber WEC. Our proposed numerical facility implements open boundary conditions, employing third-order consistent wave theory for direct generation, with flow field constrained by a Doppler correlation function. Reference data is collected from dedicated physical tests for monochromatic waves; the wave–current numerical basin demonstrates very high accuracy in terms of wave transformation and velocity field. In the second segment of this paper, a current-aware power transfer function is computed for the taut-moored point-absorber Uppsala University WEC (UUWEC). Parametrically defined regular waves with uniform currents are utilized to map an operational sea state featuring currents of different directions and intensities. In terms of power capture capabilities, the modified dynamics observed in presence of currents translates in a dependence of the WEC’s power matrix not only on wave parameters, but also on current layouts. The UUWEC’s power output has revealed that regardless of current directionality, annual output consistently decreases, with a registered power drop as high as 10% when an expected current field is introduced. • An SPH-based wave flume based on open-boundary is proposed for wave and current. • The UUWEC is investigated in a broad range of wave and current fields. • Underlying currents entail different structure dynamics increasing non-linearity. • A current-aware power transfer function is formulated. • Annual power output drops on average by 10% due to the interaction with currents.