抄録
Hydraulic model test was conducted to study the effect of Isahaya Dyke on the oceanic current in Ariake Bay. Tidal current was visualised by PIV. We found that the dyke changes the residual current in and near Isahaya Inlet very much. This may imply lower rate of water exchange in the inlet than that in the past and, eventually, possible occurrence of red tide that devastated Nori crop near the inlet. Also observed was the distribution of dye injected in the bay. The dye imitates the emitted water, which sucked from the deep layer by an apparatus called the Density Current Generator (DCG). The DCG is expected to improve the water quality under the strong stratification in summer.
