自由蛇行の発達に関する数値解析

Abstract

In this study, the numerical flow and sediment-transport model including sub-models for bank erosion considering slump block, landing process and cut-offs, is confirmed that it can indicates that the effect of discharge variation and the formation of channel cutoffs are very important factor for the natural process of river meandering. In the steady flow calculation, the shape of meandering is transmitted from upstream to downstream. The wave height and wave length which transmit depend on the discharge. But in steady flow, the meandering shape which can be seen in a natural river cannot create. In the unsteady flow calculation, in which periodic discharge variation is set, the result shows the complicated meandering process which can be seen in a natural river. The results also indicate that the numerical model which includes the bank erosion considering slump blocks, landing process and cut-offs are reasonable.