Contribution to the CCP-WSI Blind Test Series 2: CFD-based numerical wave tank experiments employing an impulse source wave maker

During the development and optimisation of wave energy converters, numerical wave tanks are useful tools, providing detailed insight into the hydrodynamic performance of devices. Specifically, computational fluid dynamics based numerical wave tanks can deliver highfidelity, high resolution, results for a wide range of test conditions. However, CFD-based numerical wave tanks come at significant computational cost and require more man-hours during model setup, compared to lower-fidelity, frequency domain based models. The computational costs can only be significantly decreased by improving the numerical solvers, or increased expenditure on computational power. The required man-hours for the model setup, however, can be reduced by streamlining the setup of CFDbased numerical wave tanks. To this end, the formulation of best-practice guidelines and benchmark test cases can expedite this streamlining. A step towards such bestpractice guidelines, and, furthermore, towards an increased confidence in CFD-based numerical wave tanks, are blind tests. This paper presents the CFD-based numerical wave tank used for the authors’ contribution to the Collaborative Computational Project in Wave Structure Interaction Blind Test Series 2. In the employed numerical wave tanks, a recently developed, self-calibrating, impulse source wave maker is implemented for the wave generation [1]. In addition to the required data for the submission to the blind test, the paper contains preliminary studies on the necessity of turbulence modelling, spatial and temporal convergence studies, as well as results for the numerical wave maker calibration.

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