1997 Volume 41 Pages 323-328
Water pollution in a semi-enclosed sea area such as a bay or a fishing port due to stagnancy of water has been a serious problem on water environment. We proposed a new method to activate the tidal exchange between an inner and an outer sea area by creation and control of a tidal residual current. In this new method, the tidal residual current is produced and controlled by artificial structures, which change properties of resistance according to a direction of flow, set on the bottom. In this study, several tidal current and particle movement simulations with various arrangements of artificial bottom roughness in a semi-enclosed model bay were carried out. As a result of many kinds of numerical experiments, it becomes clear that it is possible to generate the tidal residual current and to activate the tidal exchange by only operation of bottom roughness.
