ABSTRACT
Offshore renewable energy is a major potential source of electricity but survivability in extreme waves is a key design problem for floating platforms. Here we consider the multi-float wave energy converter (WEC) M4, a line absorber with three floats for this study and a hinge above mid float. This is modelled in focussed waves to represent extreme conditions using smoothed particle hydrodynamics (SPH) with wave basin comparison; power take off at the hinge is switched off. SPH is meshless and suited to steep, breaking waves and platform overtopping without special treatment. The open-source DualSPHysics code for fluid-structure interaction with project Chrono for mechanical constraints runs efficiently on inexpensive GPUs with many millions of particles. The versatility of the computational system is thus demonstrated for complex multi-floats with mechanical constraint and mooring (using MoorDyn library). The response measured in a wave basin is predicted well. This is the first application of DualSPHysics to such a complex offshore system.
