平原感潮河网水动力模型研究

利用一维Saint—Venant方程组、河网汊点连续方程及边界条件建立了河网水动力学模型；采用Abbott六点隐式差分格式离散控制方程组；求解河网时，将河段方程自相消元，得到以汊点水位为基本未知量的汊点方程组；采用汊点优化编码来降低汊点方程组系数矩阵的带宽以提高计算精度和节省计算耗时。对上海市平原感潮河网进行了合理概化，利用1999年6月～9月的实测水文资料进行了率定，结果表明计算值同实测值吻合较好。

Hydrodynamic model for tidal river network

Hydrodynamic model for river network is set up based on one-dimensional Saint-Venant equations, junction equations in all river junctions and boundary conditions. The control equations are discreted by 6-point Abbott implicit scheme. Firstly, the junction equations based on unknown water level are solved, then the branch equations are solved to get the water level and discharge at every section of all branches. The bandwidth of the node matrix is minimized by using optimal re-ordering of the nodal points to improve computation accuracy and reduce computation time. The river network in Shanghai area is schematized and the data observed from June to August in 1999 are used to calibrate and verify the model. It is found that the calculated results agree with the observed data very well.