人类活动影响下设计枯水的分析计算

Analysis and Calculation of Design Low Water under the Influence of Human Activities

天然河道火力发电厂设计频率97%的枯水流量,是确定电厂能否兴建及其兴建规模、确定取水口高程及取水方式的重要依据,因此,设计枯水计算是电力水文设计的重点。在受河道灌溉引水,修堤筑坝,梯级水电站、水库调度运行等人类活动影响的火电厂设计枯水流量确定,更是水文设计的一个难点。文章介绍在以往工程实践中常会遇到这些情况几种不同类型的设计枯水的计算方法,为火电厂工程设计枯水的合理利用提供依据。

The low water flow at a design frequency of 97 % for a thermal power plant at natural river channel is important to determine the possibility of power plant construction, construction scale, water intake elevation, and the way of water taking. Therefore, the calculation of design low water is the key of hydrologic design for the plant. However, it is difficult to fulfill such design under the influence of such human activities as irrigation diversion, dam construction, dispatching operation of cascade hydropower station and reservoir, etc. The paper presents different methods of calculation on design low water in case of similar conditions, providing basis for reasonable utilization of design low water by thermal power plants.