大石峡水库坝址下游河道冲淤及水位变化预测  

Prediction of Scouring and Silting and Water Level Fluctuation in the Downstream River Channel of Dashixia Reservoir Dam Site

作　　者：杜志水[1] 许慧[2] 陆杨 尚倩倩[2] DU Zhishui;XU Hui;LU Yang;SHANG Qianqian(PowerChina Northwest Engineering Corporation Limited,Xi'an 710065,China;Nanjing Hydraulic Research Institute,Nanjing 210024,China)

机构地区：[1]中国电建集团西北勘测设计研究院有限公司,西安710065 [2]南京水利科学研究院,南京210024

出　　处：《西北水电》2019年第6期17-21,共5页Northwest Hydropower

基　　金：国家重点研发计划课题(2017YFC0405206)

摘　　要：新疆库玛拉克河中下游规划有大石峡、小石峡2座水库,两坝址相距约11 km,其中小石峡水电站已建成,自2012年运行以来,库区河床抬高,对上游大石峡水库的发电尾水位有较大影响。文章运用平面二维水流泥沙数学模型预测了坝下游(大石峡水库坝下至小石峡水库坝前)在运行10、20、50年后的河道冲淤及水位变化。结果表明:①当大石峡枢纽投入运行后,由于“清水下泄”形成坝下冲刷,同流量条件下尾水渠水位将有所下降,但降幅较小。②随着河床粗化、冲刷幅度减弱,又因为小石峡坝前淤积发展,运行20年后大石峡水电站尾水渠水位反而有所上升。Two hydropower stations,namely Dashixia and Xiaoshixia,are planned in the middle and lower reaches of the Kumalake River in Xinjiang.The two dam sites are about 11 km apart.The Xiaoshixia Hydropower Station has been completed.Since its operation in 2012,the riverbed in the reservoir area has risen which has a significant impact on the tail water level of the Dashixia hydropower station.The paper adopts a two-dimensional mathematical model of flow and sediment to predict the river scouring and silting and water level fluctuation in the lower reaches of the dam(downstream of the dam of Dashixia Reservoir and upstream of the dam of Xiaoshixia Reservoir)after operation of 10,20,and 50 years.The results show that:①When the Dashixia Dam is put into operation,the water level in the tailrace channel will decrease under the same flow condition due to the scouring below dam caused by"clear water discharge".②As the river bed is coarsened and the scouring is weakened,and due to the silt development in front of the Xiaoshixia dam,the water level in the tailrace channel of the Dashixia Hydropower Station will rise instead after 20 years of operation.

关 键 词：坝下河道 河床粗化 数学模型 冲淤预测 

分 类 号：TV672.1[水利工程—水利水电工程] TV145.3