Author(s): Behzad Saeedifard; Sabagh Yazdi
Linked Author(s):
Keywords: Suspended sediment transport; Numerical modeling; Depth average; Cell center finite volume. 1
Abstract: A 2-D numerical model was developed simulating the sediment concentration variations in straight open channels. The cell centre finite volume technique was used to solve the convection-diffusion equation of The suspended sediment transport. Flow and sediment transport are simulated in a coupled manner. Two-dimensional velocity patterns and water depth of the flow field model are computed by solving the depth average equations of continuity and motion in which the effects of physical dissipations are considerable. The equations are converted to discrete form using cell centre finite volume method for triangular unstructured mesh. In order to stabilize the explicit procedure of solution, artificial viscosity terms are used. The accuracy of the model is assessed by computing the challenging case of sediment concentrations profile in a canal with a 30 meter long and comparison of the computed results with Wang and Ribberink (1986) performed experiments in a flume to study sediment transport phenomena. Wang and Ribberink (1986) test was used to study the sensitivity and error analysis of different parts of suspended load transport. In this test sediment settling velocity and non equilibrium adaptation coefficient were the only parameter to achieve the results. An empirical formula is proposed to consider the effects of the concentration on the sediment fall velocity. for the prediction of the sediment exchange rate, an alternative coefficient for non equilibrium adaptation coefficient is proposed.
Year: 2007