缺乏水文资料的复杂天然河道断面水位流量关系曲线计算

Calculation of Rating Curve at Cross Section in Complex Natural River with Few Hydrology Data

摘要: 在水电工程规划设计中，坝厂址等位置的水位流量关系曲线对于确定泄洪建筑物和消能建筑物的规模、厂房及水轮机组的安装高程、电站装机容量及发电量效益等指标的确定都具有重要的影响。但在多数水电项目的前期阶段，往往缺乏实测的水位、流量资料，只有河道的大断面资料、测时水面线及少数历史洪痕调查资料，各工程断面水位流量关系曲线往往利用上述资料根据水力学方法来推求；加之上述点位河道情况往往较为复杂，如何算出合理的成果显得比较困难和重要。本文结合工程设计实践，以工程河段河流流态较为复杂的非洲U国K水电站项目为案例，用曼宁公式、堰流公式、伯努利方程为工具，在缺乏实测水位、流量资料的前提下，推求工程坝址等特征断面水位流量关系曲线。文中的思路和方法，对于类似缺乏水文资料情况下确定水位流量关系曲线有较好的参考和借鉴作用。

Abstract: In designing and planning of hydropower project, the rating curve at dam site, powerhouse place etc. have an important effect on determining the project key parameters, such as the scale and designing of spillway and energy dissipation works, the installation elevation of powerhouse and turbine, as well as installed capacity and annual power generation amount of the project. However, in the early phase of the most hydropower projects, it often lacks gauged water level and discharge data, only the data of cross section, water level of gauged time, and few investigating historical water level data are available. The rating curve at these project feature cross sections is generally developed by hydraulic methods with these available data; what’s more, the river situation in these places is generally complex. How to get a rational result becomes more difficult and important. Combing the practical engineering design, taking K hydropower project in U country in Africa whose river channel is characterized by a complex flow regime as case study, the rating curve at project feature cross sections such as dam site is developed by the tools of the Manning formula, weir-flow formula, Bernoulli equation on the premise of lacking gauged water level and discharge data. The approach and method may provide references for a similar situation for the determination of the rating curve in the river lacking hydrology data.