Research And Application Of Hydrodynamic, Water Quality And Water Environment Capacity In The Arid Rivers

The deterioration of the water quality in rivers has become a prominent water environmental issues in our country. In the water pollution control research process, Based on the one-dimensional hydrodynamic and water quality models, studying the water capacity and a reasonable distribution for the remaining water capacity according to the water pollution situation which plays a very important role in the prevention of the water pollution.First, the thesis gives a systematic literature review for the one-dimensional hydrodynamic and water quality models as well as the water environmental capacity based on the previous research summary and the actual situation of the issue. Then the one-dimensional hydrodynamic are established on the Saint-Venant equations using the Preissmann four-point implicit difference scheme, the water quality models are established on the convection-diffusion equation using the implicit upwind difference scheme, the slot method for dealing with the moving boundary. And the models are validated by some examples. The results show that the calculated values agree with the theoretical analysis.Based on the established models, this thesis does a systematic study of the water environment capacity calculation and its allocation. In the paper, the rate of the model parameters are discussed in detail, the calculation models and methods of the water capacity are compared, and do some correlation analysis for the distribution methods of the water environment capacity and the results of the assessment.On the basis, the one-dimensional hydrodynamic and water quality models are applied to simulate the main branch of the Beiyun River, then analyze and compare the change process of the accounted results with the measured results. At last, accounting the water capacity and recommending an distribution program for the water capacity according to the water function zoning, the development of the region and the existing pollution situation, with a view to offer the Beiyun River a reference for the prediction, management and decision-making of the water quality.