Author(s): Tetsuro Tsujimoto; Tadanori Kitamura
Linked Author(s): Tadanori KITAMURA
Keywords: No Keywords
Abstract: During flood, the slower flow in the vegetated zone is neighboring to the flow in the main water course to cause an appreciable transverse mixing appears, and the flow resistance, the transverse sediment transport and the subsequent morphological change of the bed must be governed by it. In order to understand the basic mechanism of such phenomena, a fundamental study is conducted. According to the flume experiment for an idealized condition, the flow with vegetation zone accompanies an appreciable water-surface fluctuation and it maintains the transverse velocity fluctuation which is expected to bring about momentum and mass exchange between vegetated zone and main course. The correlation analysis offluctuations of water-surface elevation and velocities clarifies that an organized motion composed of low frequency fluctuations maintained each other is formed, and the the correlative structure is in phase along the depth. Even bed-load transport is affected by such a lowfrequency organized motion, and transverse flux of bed-load appears to bring about the transverse bed deformation. In this paper, the mechanism of sub-processes is formulated.
Year: 1993