The Study And Application Of Two-dimensional Flow Pollution Sediment-water Quality Coupling Model

Most pollutants' transportation is closely related to sediment and it transportion. But the sediment affection is usually ignored in deterministic model for resolving the envrionematal problem, which also affects the model's precision.Based on the previous studies, the following researches were carried out in this paper.(1) The basical problem of sediment pollution and the research results of sediment pollution water quality model are concluded firstly. Then considering aqueous phase and particle pollutants as a whole and combining the sediemt model, a sediment pollution water quality model was established. In the derivation of the model, sediment pollutant absorptive capacity, polluatant release rate from the bed sediment and its incremental rate because of sediment erosion were inducted, and by using absorption kinetics, pore water diffusion model and so on, the problem of sediment pollutant absorptive capacity and pollutant release rate from bed mud variation with temporal and spatial is solved; And Based on the understanding the mechanical meaning of shallow water, the two-dimension shallow water equation is derivated by depth direction intergral to the three-dimensional equation step by step;(2) The sediment pollution water quality model was coupling with the RBFVM-2D model (Zhao D H, 1996). Then the finite volume method is used to solve the two-dimensional flow-sediment pollution water quality coupling model. And the flux difference splitting (FDS) algorithm, an approximate Riemarm solver, is employed to estimate the normal fluxes across the interface of cell.(3)The model was applied in water simulation of Xuanwu Lake to compare different water diversion scenarios. The model was certified and verified by monitoring data in May, 2004, and then different scenarioses were desiged according to actual condition. Finally, the optimal secenarios is provided based on the analysis the water quanitiy and quality results.(4)Analyse the infection of the water quality results after taking the sediment into account.