具有明满交替流动的三峡右岸地下电站的动态仿真

Transient simulation with MFSPF for right bank underground hydropower station of the Three Gorges

以三峡电站为背景对大型水电站动态仿真的主要问题进行了研究。对几种用于明满交替流动计算的方法进行了比较分析，提出了特征隐式格式法求解明满交替流动，具有良好的稳定性；提出了管流和明流联合计算的变时步模型，在保证计算精度的前提下减少了计算量，使大型水电工程的动态仿真得以在微机上实现；提出了一种新方法（对数曲线投影法）描述转轮特性，与Ｓｕｔｅｒ法比较，新方法完全解决了转轮特性曲线描述中小开度与零开度以及多值的问题，小开度区计算结果没有异常的压力脉动，转化过程简单，运算速度快，精度高。应用上述方法编制了过渡过程仿真程序，对三峡电站的各种工况进行了动态仿真计算。

Main problems of numerical simulation of right bank underground hydropower station the Three Gorges have been studied. Several methods used for computing transient Mixed Free Surface Pressure Flow (MFSPF) were compared and analyzed. A new method (Characteristic Implicit Method) with good stability based on implicit finite difference scheme was offered. A changing time step method was developed to compute unsteady flow in pipe system connected to open channels. The method spends less computing time to get the same calculating accuracy, so that transient simulation can be done on personal computer. A new method (Logarithms Mapping Method) to represent the runner characteristics was raised up. Compared with Suter method, the new method solves the problem of the characteristic representation under small and zero wicket gate opening. When the opening is pending to zero, no abnormal waves occur in the results of the new method. Generally, the process using the new method is simple, fast and accurate.