Author(s): Mazen Omran; Serter Atabay; Donald W. Knight
Linked Author(s): Donald W. Knight
Keywords: Depth-averaged model; Secondary current cells; Boundary shear stress distribution; Depth-averaged velocity distribution; Sediment transport; Sediment concentration 1
Abstract: The phenomenon of sediment transport has an important role in hydraulic engineering. The sediment concentration in channels is often determined from equations that are based on the boundary shear stress or shear velocity. However, the distribution of boundary shear stress around the wetted perimeter of a channel is itself hard to determine. The current paper proposes a modeling philosophy based on a depth-averaged model (Shiono and Knight Method) to determine the boundary shear stress distribution in simple rectangular channels with rigid and mobile beds. The approach links the perturbation in the boundary shear stress distributions to the presence of secondary current cells and divides the channel accordingly. The philosophy is validated against experimental data and accurate boundary shear stress distributions were obtained. Despite this accuracy in the boundary shear calculation, the analytical sediment concentrations underestimated the experimental ones. This conclusion was also found when using other sediment transport equations.
Year: 2007