Combined transmission and diffraction around a floating breakwater

• Main Author: Garceau, Nathalie
• Format: Others
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/5950

Wave conditions on the sheltered side of a floating breakwater are commonly approximated by supperposing the results of the transmitted wave field across the breakwater, and the diffracted wave field around the ends of the breakwater, both obtained separately. This thesis describes an experimental and numerical investigation of the suitability of this approach. To evaluate the wave field downwave of the breakwater, three set of laboratory tests were conducted. One relates diffraction around a fixed breakwater extending to the seabed; another to the two-dimensional case of wave transmission across a breakwater located at the water surface; and the third to the three-dimensional case of combined wave transmission and diffraction past a breakwater at the water surfaces. The experiments were carried out for a rectangular caisson with three wave conditions and for both a fixed and freely floating breakwater. Three numerical models of a rectangular breakwater based on linear potential theory were used to predict results relating to transmission coefficient in the case of wave transmission only, wave diffraction only and combined wave transmission and diffraction. The results from the laboratory experiments and the numerical models were compared to validate the numerical models. Also, the addition of the transmission and diffraction solutions were compared with the combined solution, on the basis of experimental results as well as numerical results. The numerical and experimental results have indicated that the superposition approximation generally overestimates the combined situation, particularly for longer waves. === Applied Science, Faculty of === Civil Engineering, Department of === Graduate