Cogent Engineering (Dec 2022)

On the placement of a wave manipulator suitable for energy harnessing in the Nearshore

  • K. D. R. Jagath Kumara

Journal volume & issue
Vol. 9, no. 1


Read online

The effectiveness of a wave manipulator which is used for enhancing the nearshore wave energy density is described in this paper. The manipulator is formed by cascading a converging, uniform, and a diverging channel section for concentrating, stabilizing, and dispersing the waves, respectively. The linear wave theory, mode theory for open channel wave propagation, and some semi-empirical formulations are used for estimating the wave parameters at various points of interest and the location of wave breaking. Further, a regression formula is presented to estimate the phase velocity in the inner surf zone. The energy density and flux are quantified before and after wave breaking inside the manipulator. It is shown that the procedure is most effective if the entrance of the manipulator is placed at the shoaling region but closest to the shore. If the waves are not broken, the relative increase in the energy flux is equal to the level of concentration but that of broken waves is still high enough for energy harnessing. It is also shown that either wave energy convertors or hydro turbines could be used for energy harnessing by setting the dimensions of the manipulator appropriately. Finally, the other advantages of the manipulator are discussed.