向家坝枢纽非恒定泄流对落锅滩河段航道通航条件的影响

电站日调节非恒定流对下游河道的影响是向家坝工程在运行时需要考虑的主要问题。通过长河段二维非恒定数学模型计算分析向家坝日调节非恒定流对落锅滩河段航道通航水流条件的影响,选取两种典型日调节工况和泄洪工况分析河段内水位、流量、流速等水力因素变化特性。结果表明,两种典型日调节工况下非恒定流传播至落锅滩水位变幅在1. 26～1. 46 m,泄洪工况下水位最大日变幅在2. 05～2. 96 m,非恒定流对河段产生了一定影响,根据目前通航标准来看,4种工况下河段内水力指标均能够达到通航水力指标。建议对坝下非恒定流特征及其对航道、港口码头的影响情况进行原型观测,积累实践经验,为进一步优化电站调度方案和下游航道维护等方面提供依据。

Influence of Xiangjiaba unsteady flow on waterway navigation conditions in Luoguotan reach

The influence of daily unsteady flow regulation on the downstream channel is the main problem to be considered in the operation of Xiangjiaba Project.Based on the two-dimensional unsteady mathematical model,we analyze the influence of daily unsteady flow of Xiangjiaba on the navigation conditions of the waterway of Luoguotan reach,and select two typical daily regulating conditions and two flood discharge conditions to analyze the variation characteristics of water level,discharge and velocity in the reach of the river.The results show that,under two typical daily regulation conditions,the variation of water level from unsteady flow ship to Luoguotan is from 1.26 m to 1.46 m,and the maximum daily variation of water level under flood discharge condition is from 2.05 m to 2.96 m.The unsteady flow has a certain influence on the reach of the river.According to the current navigation standard,the maximum daily variation of water level is from 2.05 m to 2.96 m.Under four conditions,the hydraulic index of river reach can reach the navigable hydraulic index.The characteristics of unsteady flow under the dam and its influence on the waterway and port wharf should be observed prototype,accumulate practical experience,and provide the basis for further optimization of power station scheduling scheme and downstream waterway maintenance.