ON THE CHARACTERISTICS OF FLOW MOVEMENT IN THE BENDING AND BIFURCATED RIVER

摘要

The bending and bifurcated river is one kind of braided river, this river pattern has the evolution characteristics of both bending and bifurcated river, so its evolution is complex.Although each reach has its own specialty, but all follows the identical basic rule of current movement and adjustment to scouring and silting of rive bed. This paper takes the example of the reach of Yangtze river in Yidu, which is a typical shallow-water bending and bifurcated reach, uses CCHE2D numerical model to simulate the water movement of Yidu reach, and analyzes the water movement charicteristics of Yidu reach based on the simulation result. The variation of the velocity distribution of flow and the local water surface longitudinal slope along the distance and with the change of water discharges is ananlyzed. At last, The position of dynamic axis of flow of bending and bifurcated reach with different discharges is ananlysed.