A coupled hydrodynamic–structural model of the M4 wave energy converter

Abstract

a b s t r a c tA method is developed for modelling wave energy converters consisting of floats connected by slender structural elements. The hydrodynamic and structural dynamic analyses are separated in a two-stage process, though the model is fully coupled. The method of dynamic substructuring is used to achieve this separation. The linear diffraction/ radiation problem is solved with a finite element idealisation for axisymmetric floats, and drag forces are incorporated by equivalent linearization. Results for a planar representation of the M4 device, and comparisons of theory and experiments undertaken for two scale models tested in regular and random waves, confirm the validity of the theoretical approach. A series of parametric studies is performed to clarify the important physical variables, including natural periods, the ratio of a characteristic length of the device to the wave length, and power take-off.

Non-causal Linear Optimal Control With Adaptive Sliding Mode Observer for Multi-Body Wave Energy Converters

“…, r = 0.08 (25) , as suggested in [22]. The sampling time is T = 0.009 s. The following 4 sets of simulation are done.…”

Performance Analysis of a Floating Wind–Wave Power Generation Platform Based on the Frequency Domain Model

“…Additionally, the Capture Width Ratio (CWR) is a crucial metric for assessing the efficiency of a WEC in capturing wave energy. It can be expressed as follows [49]:…”

On the Development of an Offshore Version of the CECO Wave Energy Converter

“…Fixed devices, such as the Wave Star [12], absorb energy from one DoF and have only one mode of motion. In contrast, floating devices may have multiple modes of motions and eventually absorb energy from one or two DoFs, as examples Pelamis [13], Weptos [14], and M4 [15] WECs. Only a few alternative designs, based on oscillation along an inclined axis, have been proposed [16,17].…”