Catenary moorings for offshore floating structures
Each year more energy resources are exploited to meet the needs of current society. These new energy sources are mainly located at sea, such as oil & gas, off-shore wind farms, and wave/tide energy devices. Off-shore applications present a new field of study in engineering. These applications have demanded new functionalities that were implemented in DualSPHysics.
DualSPHysics code is coupled with MoorDyn, an open-source dynamic mooring line model. MoorDyn (www.matt-hall.ca/software/moordyn) has been developed by Matt Hall (University of Prince Edward Island, Canada).
The coupling between DualSPHysics and MoorDyn has been validated using laboratory tests of a floating solid box moored to the wave flume bottom interacting with regular waves. The box dimensions are 0.2 m x 0.2 m x 0.132 m with a total weight of 3.163 kg. The centre of gravity of the box lies at (0, 0, -0.0126) m. In DualSPHysics, the box geometry is generated as a set of SPH particles with density of 600 kg/m3 (same as the material used for the physical scale model). The box is moored to the bottom using four chains. The numerical free-surface elevation at different locations, the motions of the floating solid box (heave, surge and pitch) and the tensions in the mooring lines are compared with the experimental data.
The experimental tests have been carried out at the large wave flume of Ghent University. They are preliminary tests for the experimental campaign of the "EsflOWC" project (Efficiency and Survivability of floating Oscillating Wave Energy Converters moored to the seabed) funded by the EU HORIZON2020 MaRINET2.