【作者】 梅金娟；

【导师】 李光炽；

【作者基本信息】 河海大学 ， 城市水务， 2007， 硕士

【摘要】 分析当前长江下游河段地区洪水的危害性、防洪的重要性及该河段水位预报的主要问题和困难，论文研究了河道洪水演算模型：基于完全圣维南方程组、利用四点线性隐格式离散，根据长江下游地形以及地理位置的情况，引入反分析法模拟支流流量，建立一维水动力学模型。经过实例验证，表明了模型能够模拟长江下游河系的实际流态，具有一定的精度，可以应用于水位预报。研究了感潮河段一维水动力学模型中的下边界条件的预报问题，根据感潮河段的水位影响因素，用考虑日平均水位的调和分析法预报下边界条件，并尝试用同样的方法预报感潮河段控制站的水位。经计算验证，预报精度能够满足洪水预报的要求。分析将一维水动力学模型和调和分析算法在长江下游河段的应用。比较它们的结果。显示一维水动力学模型较好，模型可以包含实时校正的过程，具有很好的实用价值，调和分析算法对具有长期水位观测资料的控制站，预报水位具有一定的精度，它为缺少断面资料感潮河段的水位预报探索一条新途径。更多还原

【Abstract】 To analysis damages of flood in current downstream of Changjiang River, the importance of the flood control, the key problems and the difficulties of water level forecasting in the reaches, the paper studied models for channel flood routing: to base on St.Venant equations and be solved with four-point linear implicit schemes, according to terrain as well as geography position is considered, to introduce the reverse direction of analytical method to simulate flux of every branch, and then one-dimensional hydrodynamic model is constituted. The validation result shows that with this method can simulate practicable flow pattern and possess certain precision, and then it can be used to water level forecast.Forecast of the lower boundary condition in tidal reach’s one-dimensional hydrodynamic model is researched. According to influencing factor of tidal reach’s water level, harmonic analysis is used to forecast the lower boundary condition, which has thought over daily mean water level. The validation result shows that precision of prediction can satisfy flood forecast’s demand.The application of the one-dimensional hydrodynamic model and harmonious analysis method in Changjiang River is analyzed, the results of which are then compared. The result shows that one-dimensional hydrodynamic model is preferable. At one time, the model contains real time correction, so that it is banausic. Harmonious analysis method is used to forecast key station of long-time water data, and it can ascertain definite precision of forecasted. It present a method for water regime predictions if tidal rivers in defect of cross-section.更多还原