Author(s): Zhu Yuliang
Linked Author(s):
Keywords: Numerical model; River networks; Junction control method; Unsteady flow; Suspended-sediment transport
Abstract: A numerical model for simulating unsteady flow and suspended-sediment transport in river networks is presented. This model is based on the Saint-Venant equations and the non-equilibrium transport equation for the suspended-sediment, and the junction control methods for water level and sediment concentration are established. First, utilizing the transforms of the single river finite-difference equations and the mass and energy conservation at the river junction, the control equations for all junctions' water level can be written in matrix notation. the water level at all junctions are obtained by solving the irregular spare matrix equations, then the water level at all single river nodes are gotten by the solution algorithm for the single river unsteady flow. The solution algorithm for the sediment transport in river networks is similar to that for unsteady flow. This paper presents a junction control method for suspended-sediment in river networks. Assuming the erosion and deposition at the junction is small, the control equations for all junctions' sediment concentration also can be written in matrix notation by the sediment mass conservation equation. Solving the irregular spare matrix equations, the sediment concentration at all junctions are obtained. The sediment concentration at all single river nodes are gotten by the solution algorithm for the single river suspended-sediment transport. The model presented in this paper is applicable to all river network types. As a check, the model is successfully used in the Pearl river networks.
Year: 2001