山区河流小型水电站回水末端计算

Computation of backwater end for small hydropower station on mountainous river

以广西绣江交口电站为例,通过综合利用正坡缓流水面线的基本特征、水动力数学模型以及电站水位-流量关系曲线等,确定不同流量时电站坝址处的天然水位,为山区河流小型水库在缺少天然资料时进行回水计算提供一个应用实例。交口电站回水计算结果表明:影响回水末端的主要因素是回水末端判别标准精度高低、来流流量大小,以及坝前水位高低等。回水末端判别精度越高或坝前水位越高,回水末端越趋向于上游;来流流量越大,回水末端越趋向于水库大坝。

The hydraulic theory, hydrodynamic numerical model and stage-discharge curve were used together to determine the water level of the Jiaokou Hydropower Station under the natural condition at different discharges, the hydropower station being located on Xiujiang River in Guangxl Zhuang Autonomous Region. The study gives a successful example of backwater end computation for small hydropower stations in the case of lack of measured data. The result of computation indicates that the main affecting factors include the criterion for backwater end determination, the volume of discharge and the operating level of the reservoir. With the improvement of the precision for determination of the backwater end and the rise of the operating water level of the reservoir, the backwater end moves towards the upstream, while it approaches to the dam if the discharge is increased.