Two dimensional modelling of sediment transport in unsteady flows

In this dissertation a two-dimensional, depth averaged, coupled model in equilibrium and non-equilibrium conditions has been introduced to calculate the treatment of water surface profiles and bed deformation in alluvial channels and rivers. This coupled model made of three components, named meshing component, hydrodynamical component and morphdynamical component. The first component, develops triangular, unstructured meshes to discritisize the domain of the flow in open channels or rivers. The second component, applies two dimensional shallow water equations to calculate hydraulic data. The last component by considering the values that calculated by the second component and employing continuity equations of sediment transport phenomenon and various required experimental relations, determine bed deformation in erodible layer. Furthermore, in order to simulate the reality of the nature world, two turbulence models have been supplemented to the governing equations. For the sake of discretizing the governing equations Finite Volume Method has been employed in explicit conditions. In addition, Total Variation Diminishing scheme has been employed to solve the governing equations. In order to fill the gap of experimental research and examine the numerical results of developed model, Flow3D software has been used. Results from the four hypothetical cases show good agreement with the numerical results of Flow3D software.