Interaction between Main Channel and Flood-Plain Flows

Abstract

The experimental results presented in this paper have demonstrated the transport of longitudinal momentum from the main channel to the flood plain. This transport increases the bed shear stress in the flood plain and produces the opposite result on the main channel. The velocity profiles in the region affected by this interaction have been found to be similar if viewed with respect to the undisturbed flow in the flood plain. The velocity and length scales have been correlated with mainly the ratio of the depth of flow in the main channel to that in the flood plain. In the present experiments, the main channel was narrow and thus the interaction extended inwards to the center line of the main channel. For the concepts introduced in this paper to be used in solving practical problems, further experiments should be conducted with wider main channels including the effects of bed roughness.