DualSPHysics has been employed to simulate the three main experiments conducted during the design stage of a wave energy converter (WEC): a radiation test, a diffraction test, and a dynamic response test. In the radiation test, the numerical heave motion of the device for a monochromatic multisine force signal was validated against experimental data, where a broad spectrumpoly-chromatic signal was used to build an impedance model via system identification. The model allowed obtaining key hydrodynamic parameters of the point-absorber, such as the added mass and the radiation damping. The numerical results obtained were compared with experiments and with output from the linear potential solver WAMIT. During the diffraction test, the device was completely locked and subjected to incoming waves; the forces exerted on the WEC by regular waves were measured and compared with the experimental ones. Finally, the dynamic response test includes both waves and forcing from the power take-off(PTO)system. The dynamic response of a closed-loop system ,in which the applied PTO force depends on the position and velocity of the device at each time instant. For all these tests, DualSPHysics proves to be capable of being used in the design of WECs.