An Experimental Study on Reaeration by a Breakwater Generating Vertical Circulation Flow

In summer seasons severe hypoxia or anoxia has been generated near the sea bottom in enclosed seas. In order to restrain the hypoxia and anoxia, authors have developed a new breakwater which generates vertical circulation flow. Hydraulic effectiveness of the developed breakwater has already been verified. In this study, reaeration characteristic of the developed breakwater is examined by laboratory experiment. At first, the reaeration coefficient k2 is estimated from the data of dissolved oxygen in a reaeration volume with different water depths. Furthermore, substance transfer coefficient KL, is calculated from the estimated k2. Finally, KL of the proposed breakwater is compared with Kr, of other structures such as the slit-type caisson or rubble mound breakwater.