PERFORMANCE OF A DOUBLE-CURTAIN-WALLED BREAKWATER WITH A FRONT WALL OF INCLINED PLATE ARRAY

In order to mitigate secondary effects caused by high reflection waves from a curtain-walled breakwater, a new type of curtain-walled breakwater was proposed. It consists of two vertical walls with different draft depths. The distance between the two walls is comparatively narrow, e. g., having a similar size to the width of its super structure. The mechanism of effective dissipation of wave energy is to enhance the generation of vortex flows from the curtain walls, especially from the front curtain wall placed on the offshore side, which consists of an array of inclined plates with the same gap. By using the wave resonance of Helmholtz mode between the two walls, enhancement of the vortex flow is realized. In the experimental and theoretical examinations, changing the water depth and the distance between the two walls, important hydraulic properties of a double curtain-walled breakwater, such as reflection and transmission coefficients, wave energy dissipation rates and so on, are clarified.