Experimental work on breakwaters with wave energy

Here we propose a hybrid breakwater design which incorporates a wave energy converter into a slotted breakwater. We combine a well studied wave energy converter known as an Oscillating water column or OWC with a slotted breakwater. Results show that by combining these two energy dissipating mechanisms can lead to significant improvements in the energy extraction of the OWC, while also improving the breakwater in terms of blocking waves from entering the harbor. For more details feel free to have a look at our journal publication: “A Dual-Function Design of a Slotted Breakwater with a Rectangular Oscillating Water Column: A Wave-flume Study” published in Energies.

Over the course of the experiment, we also learned a valuable lesson in working with narrow wave flumes. When working with a narrow flume or larger flumes with concrete sidewalls, care must be taken due to the viscous dissipation of energy along the sidewall. This can significantly impact wave transmission and reflection measurements as we typically measure at a distance away from the structure to avoid interference of evanescent waves. In this paper we consider viscous damping due to sidewall friction by employing an exponential decay similar to Stiassnie et al. (1984). The damping parameter is obtained through empty flume tests, measuring the wave height decay along the flume length.

Front view of the structure: