The water pollution in a harbor is one of the most crucial topics today.In order to improve the sea water quality in a harbor, it may be estimated that water exchange ability through harbor breakwaters is important. Such water exchange may be realized by adopting permeable breakwaters, including the new type breakwater with special overtopping works in it.
In this study, we examined the mass flux through the harbor entrance and the permeable breakwater to understand the resultant flow field in the model harbor basin. We also carried out the experiment on the comparative case, in which impermeable breakwaters were used instead. It was observed that the direction of mass flux through the permeable breakwater is toward inside the harbor. On the contrary, that is toward outside the harbor through the harbor entrance. In the case of permeable breakwater, the vertical mixing of water appears under the condition that the strong vortex flows are generated around the permeable breakwater.
