Experimental study on hydrodynamic characteristics of a new type floating breakwater with opening pass and wing structure

To attenuate long-period waves better, a new type of floating breakwater (FB) with an opening pass is proposed. When the waves act on the FB, the wave can spray upward along the radian opening and convert part of the kinetic energy of the incident wave into potential energy. This will lead to wave breaking, which improves the wave elimination efficiency. In addition, the new type of FB design with an arc-shaped wing structure under water improves the damping effect and induces wave slamming and breaking phenomena on the back wall. A series of experiments, including a traditional dual-box FB and five new type FB models with different outlet radii, were carried out to investigate and compare the hydrodynamic performance. The results show that, with the same weight and principal size, the transmission coefficient of the new type of FB was 8.2%–17.8% smaller than that of the traditional dual-box FB in long-period and large-amplitude waves. In addition, the new type has smaller mooring forces and heave responses. A smaller outlet radius of the opening pass can give rise to a higher water spraying phenomenon, but the outlet radius generally has a small effect on the hydrodynamic performance and the mooring forces. •A new type of floating breakwater with innovative wave attenuation mechanisms is proposed.•A series of model experiments were carried out to investigate the hydrodynamic performance and the mooring forces.•The proposed model has a significant improvement in wave elimination efficiency.•The water spraying phenomenon and wave slamming phenomenon were observed in the test.•A smaller outlet radius of the opening pass can give rise to a higher water spraying.