南水北调中线工程输水建筑物整流累积效应研究

为分析输水建筑物整流对南水北调中线工程输水能力的影响,以陶岔渠首闸至十二里河渡槽渠段为例,建立一二维耦合水动力模型,其中渠道段采用一维模型,4个输水建筑物段(刁河渡槽、湍河渡槽、严陵河渡槽和淇河倒虹吸)采用二维模型,利用多年实测数据对耦合模型进行率定。分别对无整流方案和15种整流方案进行模拟计算,分析不同整流方案对上下游的影响,进而确定水头损失最小的整流方案。结果表明:单体整流影响范围为建筑物上下游3~5.km,多个建筑物整流的累积效果小于单个建筑物整流效果的线性叠加；对渠段中间2个输水建筑物(湍河渡槽、严陵河渡槽)进行整流的效果优于对上下游2个输水建筑物(刁河渡槽、淇河倒虹吸)进行整流的效果。

Study on cumulative effects of rectification on water conveyance structures in Middle Route of South-to-North Water Diversion Project

In order to analyze the impact of rectification of water conveyance structures on the water diversion capacity of the Middle Route Project of the South-to-North Water Diversion Project, taking the section from the gate of Taocha canal to the Shierlihe aqueduct as an example, a coupled one- and two-dimensional hydrodynamic model was established, with the one-dimensional model adopted for the channel section and the two-dimensional model adopted for the sections of the four water conveyance structures (the Diaohe aqueduct, Tuanhe aqueduct, Yanlinghe aqueduct and Qihe inverted siphon). The coupled model was calibrated with multi-year measured data. Fifteen rectification schemes and a scheme without rectification were simulated to analyze the impact of different schemes on the upstream and downstream sections and to explore the rectification scheme with the minimum head loss. The results show that the impact range of rectification is from 3 to 5 km upstream and downstream of a single structure and the cumulative effect of multiple structures is less than that of the linear superposition of single structures. The effect of rectification of the two water conveyance structures (the Tuanhe aqueduct and Yanlinghe aqueduct) in the middle of the channel section is better than that of the two water conveyance structures (the Diaohe aqueduct and Qihe inverted siphon) in the upstream and downstream sections.