ABSTRACT
In order to investigate the channel migration processes with multi-thread flow, a physics based morpho-dynamic model has been developed which comprises a depth-integrated hydrodynamic model for rapidly varying unsteady flows and a non-uniform sediment transport model for morphology evolution. The sheltering effect for non-uniform sediments and the influences of bed slope and secondary flow are taken into account in the sediment transport model. The model is applied to an experimental braided river and that the numerical model predicted channel patterns are shown to generally resemble the experimental observations. The model is capable of reproducing the main features of morpho-dynamic processes, including the channel evolution from a straight channel to a curved channel, from a singlethread channel to a multi-thread pattern, and the local morphologic changes such as the inception, development and disappearance of bends, bars, bifurcations and confluences.
