抄録
In braided channels, channels vary spatially and temporally, which results in the big variation of the sediment dischrge. It is important to know the channels pattern and process of stream channels variation. Channel patterns can be predict by the length and width of each stream channel. In this paper, two dimensional simulation model are employed to clarify the process of sand bar formation and channel diverging phenomenon in a gradually widening channel, in order to investigate the length of a stream channel. The results of the calculation are compared with the data obtained from flume tests to verify the numerical model.