Design of the Wave Dragon Mooring System: setup of a numerical model for time-domain analysis

This report is part of the project “Wave Dragon 1.5 MW North Sea Demonstrator”, funded by the Danish Energy Agency under the EUDP program (J.no. 64010-0405). In phase 1 of the project the hydrodynamic characterization of Wave Dragon was carried out through numerical analysis with a model calibrated with experimental data, derived from tank tests of the 2nd generation scaled model of the device.
In phase 2 further tank testing has been carried out on a novel 3rd generation scaled model to assess the design loads in the mooring system and the extreme response of the device in surge, heave and pitch to extreme storm conditions typical of the DanWEC location. The most desirable mooring configuration has also been better defined in terms of horizontal compliance.
In phase 3 results from phase 1 shall be used to setup a numerical model for time-domain analysis of the composite system Wave Dragon + moorings. Alternative mooring configurations have to be assessed in order to identify the most cost-effective, real configurations allowing the desired compliance to the system, as shown by the results of phase 2. The numerical model used is part of the commercial software package SESAM, developed by DNV together with Marintek.