Research And Application Of Two-Dimensional Water Quality Model For Water Resources Protection

A depth-averaged two-dimensional river water quality model is developed for water resources protection. The basic equation of the finite volume method, FVM, is obtained, using the divergence theorem. Meshes are used to represent the computational domination. In the framework, a finite volume method on a structured or an unstructured grid has been developed. The model transfers 2-D problem to a series of local 1-D problems. Firstly, the mass and momentum fluxes through each mesh are calculated according to the balance theory. Then the water elevation and depth-averaged velocity of each mesh are obtained.One of the attractive features of this model is to treat the calculation of the mass and momentum flux across with the flux vector splitting scheme (FVS). It uses the merits of the finite difference method and the finite element method. The model employs FVS-type approximate Riemann solver to estimate the numerical flux across the interface among cells with high accuracy.The model has been examined and verified by on-the-spot survey datas of WuHan section of Yangtze river and HanJiang river. The results show the water-quality characteristics of the studied watercourse. It is proved that the model is validating reasonable and applicable. In the environmental managing works, the model can be used to analyse transfer and degradation of contamination and predict the relationship between the area of the belts and the discharged pollutions.In the example of the argumentation of the point source pollution of WuHan breach of Yangtze river, the paper construes the influences which the discharged industrial waste water does to the studied water area on condition of normal and accidental discharged. The model computes the main pollutant mixed belts in generalized pollution point, and the relationship between the area of the belts and the discharged pollutants. The water quality of the river and suitable pollution control measure are given.Sample applications of this model to the non-point pollution flow of WuHan breach of HanJiang river, as to rough estimate storm runoff and pollution loading in HeShan Area of WuHan city. Based on the hereinbefore works, the paper analyse the main pollutant mixed belts and relationship between the area of the belts and the discharge pollutionwhen it is discharged in the manner of normally, or accidentally, or treated . On the reasoning of area source of storm runoff discharged in city , the paper commence a good attempt.Results calculated with the design method suggested that the model can meet the environmental engineering requirements. Additionally, the model is improved to simulate the flow affected remarkably by tide and river bend. The model can be practically generalized to managing works of water resources.