Study On Application Of Hydrodynamic Model In Hydrology

China is a country in which drought and flood has often happened. Water conservancy is playing important role in national economy. The development of water conservancy has a direct influence on the stability of nation and the level of people's life. Today, age of science and technology change with each passing day, development of water conservancy must fit for the demand of modernization. Science of water control required a tool of science. Hydrodynamic model is important tools of river flood routing and flood control, promote the beneficial and abolish the harmful, technically water control and scientific water manage. Based on the characteristics of drainage basin, the variable weighted method has been integrated into Xin'anjiang Model to calculate the areal rainfall, the distortion is reduced for asymmetry of rainfall and the different center of rainstorm. Because of the difficulty for forecasting water level in plain basin using hydrology method, a hydrodynamic model is brought forward. It can be preferable consider the influence of backwater to forecast water level in plain basin by coupling hydrodynamic model and hydrology model.According to different hydraulic characteristic of flood and ebb tide, Manning Coefficient is calibrated separately to calculate water level and discharge at each section on successive periods by applying the Saint-Venant equations with differential method. The model is applied to analyse the demand and supply of water resources in plain and simulate the tidal-discharge in Ningbo City. The results show that the calculated discharges are closed to the observed values, this model is practicable and it can widely used in yield by improving.