CFD Simulation of Wave Energy Converters in Focused Wave Groups Using Overset Mesh

This paper presents the numerical modelling of two point absorber wave energy converters (WECs) with and without a moonpool under focused wave conditions. The numerical model applies the overset mesh technique in order for the mesh to conform with the large-amplitude WEC motion induced by the focused wave groups. The incident wave group is first examined by a mesh convergence test and by comparing with the experimental data. The simulations are then carried out with the presence of the WEC. In total, three wave conditions are considered, each with the same wave period but with different wave heights. Nonlinear effects on the WEC motion are clearly exhibited when the wave steepness increases. The accuracy of the numerical results is carefully assessed against experimental data. Furthermore, the effects of the moonpool on the dynamics of the WEC are also discussed, where the WEC motion is compared for the case with and without a moonpool under the same wave conditions.