development of a 2d depth-averaged model for calculating scouring and deposition in alluvial streams

A depth-averaged 2d model is developed to study deposition and scouring in rivers. to calculate the bed load, different empirical formulas were implemented. a twodimensional depth integrated convection-diffusion equation was solved to determine the suspended load. this study also considered different widely used empirical relationships to determine the sediment exchange term with the bed in the suspended load equation. the model was used for calculating the scouring and deposition in two complicated cases of scouring in a bridge location and scour-hole migration in an erodible channel bed. the results of the model were then compared with experimental measurements as well as 3d numerical model results given in the literature. based on these comparisons, the most appropriate combination of the empirical formulas for sediment exchange coefficient and sediment load to be used for computing scouring and deposition is introduced. the results of numerical simulations confirmed the applicability of the proposed model in river engineering for design purposes.