Abstract
Large-scale coherent vortices with vertical axes due to the shear instability are generated at the junction between a main channel and a flood plain in compound open channel flows. Prediction of unsteady flow structures induced by the vortices is important for flood control because the vortices affect the resistance of the flows. A non-linear k-ε model is applied to compound open channel flows with different depths and the predicted flow resistances are compared with experimental results and the results by a divided-area method. The difference of the results between quadratic and cubic non-linear models is also discussed.
