黄河-渭河交汇处水流结构与河道演变实测结果分析  

Flow Structure and River Evolution at the Confluence Between Yellow River and Weihe River

作　　者：林昊 张汇明[1,2,3] 张同强[4] 徐磊[1,2] 王平[1,2] 万安[1,2] 凌宇翔 LIN Hao;ZHANG Hui-ming;ZHANG Tong-qiang;XU Lei;WANG Ping;WAN An;LING Yu-xiang(The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210098,China;College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;Key Laboratory of Water Cycle and Hydrodynamic Systems of the Ministry of Water Resources,Hohai University,Nanjing 210098,China;Hydrology and Water Resources Bureau of Sanmenxia Reservoir of Area Yellow River Water Resources Commission,Sanmenxia 472000,China)

机构地区：[1]河海大学水灾害防御全国重点实验室,江苏南京210098 [2]河海大学水利水电学院,江苏南京210098 [3]河海大学水利部水循环与水动力系统重点实验室,江苏南京210098 [4]黄河水利委员会三门峡库区水文水资源局,河南三门峡472000

出　　处：《水电能源科学》2024年第6期68-72,共5页Water Resources and Power

基　　金：国家重点研发计划(2022YFC3202601,2022YFC3202602);国家自然科学基金项目(52079044)。

摘　　要：黄河-渭河交汇处是黄河流域典型的大型河道交汇处之一,亦是中下游水动力和泥沙输移的重要控制节点。为进一步认识该处大宽深比、高含沙、复杂地形条件下的三维水流结构及河道演变规律,运用声学多普勒流速剖面仪(ADCP)对该交汇处15个横断面的流场进行现场测量,采用动能校正系数(α)和动量校正系数(β)分析水动力调整过程。通过遥感影像数据提取河道平面形态,分析交汇处及上下游的河道演变规律。结果表明,黄河-渭河交汇处可观测到明显的停滞区、最大流速区、流速恢复区等水动力特征区;拐角处未发现明显分离区,主要是因为该处河道过渡平顺。黄河与渭河交汇初期,由于流速差异大和河道缩窄导致流速不均匀性较强,α、β分别约为1.5、1.2,随着河道向下游展宽,流速不均匀性迅速减小。交汇处断面内存在较强的二次流,其流速可达主流流速的1/8,并向下游衰减。遥感研究表明交汇处所属黄河河段不稳定,且存在顶点的岸线淤长和对岸的岸线后退现象。The confluence of the Yellow River and the Weihe River is one of the typical large-scale river confluences in the Yellow River Basin,and is an important node for hydrodynamics and sediment transport in the middle and lower reaches of the Yellow River Basin.In order to further understand the three-dimensional flow structures and river evolution under the large width-to-depth ratio,large sediment load and complex topography,the flow fields of 15 cross-sections at the confluence were measured in site by acoustic Doppler velocity profiler(ADCP),and the hydrodynamic adjustment process was analyzed by kinetic energy correction coefficient(α)and momentum correction factor(β).The plan form of the river channel was derived from the remote sensing image data,and the evolution of the river channel at the confluence and upstream and downstream was analyzed.The results show that the hydrodynamic characteristics,such as the stagnation area,the maximum flow velocity area and the flow velocity recovery area were observed at the confluence of the Yellow River and the Weihe River,while obvious separation area was not found at the corner possibly due to the smooth transition of the confluence channel.At the beginning of the confluence,the inhomogeneity of flow velocity was strong(about 1.5 and 1.2 for theαandβ,respectively)due to the large difference in velocity between the two flows and the narrowing of the channel.The values decreased rapidly with the widening of the river channel along the downstream.A strong secondary flow occurred in the cross-section at the beginning of the confluence,and its flow velocity can reach 1/8 of the main flow velocity.The secondary flow velocity decreased to the downstream.The remote sensing results demonstrate that the reach of the Yellow River which the confluence belongs to was unstable,and the confluence itself suffered from the deposition near the apex and the erosion near the opposite bank.

关 键 词：黄河-渭河 河流交汇 ADCP 水流结构 二次流 河道演变 

分 类 号：TV147.4[水利工程—水力学及河流动力学]