Research On The Hydrodynamic And Water Quality Coupled Numerical Model For Dajingshan Reservoir

Dajingshan Reservoir, a middle reservoir located in Zhuhai, is the important water source supplying drinking for Zhuhai and Macao. Water quality investigation in 2005 showed that its average trophic state index was 53.94, which has indicated a low eutrophicated reservoir. Therefore the water eutrophication's analysis and control for this reservoir is very valuable. An one-dimensional hydrodynamic and water-quality coupled model was constructed for Dajingshan reservoir. The model was calibrated with hydrodynamic and water-quality data obtained from 2005. The in time distributions of water level, temperature, dissolved oxygen and other nutrients were simulated by the model. The results showed these simulations agreed well with the measurements. The calibrated model can represent the characteristics of hydrodynamic and water-quality of Dajingshan Reservoir. So it is validated in reservoir's management.The parameter research was made by this model. Effects of the water initialized temperature and the elevations of outlet and inlet were investigated. The influence of natatorium nearby on the water quality of the reservoir's surface layer and simulations of algal growth response to increasing of the inflow nutrients were also studied. The results showed that if the water initialized temperature was unknown, putting ahead the model calculation time step forty Julian days, the computed results represent real dates. Effect of the outlet and inlet elevation in reservoir on the surface layer water temperature is trivial, however, in some season the deep outlet can increase the deep layer's water temperature notable. During the opend period of the natatorium nearby, the total phosphorus increases significantly. The influences of pollutants by tourism are more obvious when both inflow and water level of the reservoir are low. Simulations of algal due to increasing of nitrogen and phosphorus loads demonstrate that the algal growth is limited by phosphorus in the reservoir.Finally, a net model was established. Based on the knowledge of pollution tend of Dajingshan Reservoir, the research of in net water transporting effect on water quaility of Dajingshan Reservoir was carried out. The analysis reveals that the volumn of transporting water is the key to the net's water quality...