黄河下游典型概化心滩绕流近壁面流场水力特性  

Hydraulic characteristics of flow field near wall of typical generalized mid-channel bar in Lower Yellow River

作　　者：张春晋 任小凤 张敏[1] 丰青 赵崇旭 ZHANG Chunjin;REN Xiaofeng;ZHANG Min;FENG Qing;ZHAO Chongxu(Key Laboratory of Lower Yellow River Channel and Estuary Regulation Sediment,MWR,Yellow River Institute of Hydraulic Research,Zhengzhou,Henan 450003,China;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing,Jiangsu 210098,China;Henan Yellow River Hydrology Reconnaissance&Design Institute Co.,Ltd.,Zhengzhou,Henan 450004,China)

机构地区：[1]黄河水利科学研究院水利部黄河下游河道与河口治理重点实验室,河南郑州450003 [2]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [3]河南黄河水文勘测规划设计院有限公司,河南郑州450004

出　　处：《排灌机械工程学报》2024年第11期1120-1127,共8页Journal of Drainage and Irrigation Machinery Engineering

基　　金：黄科院发展基金资助项目(202006);黄河水科学研究联合基金资助项目(U2243220);水利部泥沙科学与北方河流治理重点实验室开放基金资助项目(IWHR-SEDI-2022-07)。

摘　　要：为了揭示黄河下游典型概化心滩绕流近壁面流场的水力特性,以下游马峪沟断面附近典型心滩作为研究对象,利用模型试验与数值模拟探究不同流量与水深条件下概化心滩绕流近壁面流场的水流流态、河床高程、水流挟沙力及床面阻力等特性,并验证平面二维水沙模型计算得到的流速分布与河床高程的正确性.结果表明:分流区断面受到滩头影响,流速变小,并且流速最大值出现在汊道.汇流区断面在滩尾影响下发生边界层分离,水槽中央流速达到最小,此后流速达到最大并趋于平均化;采用平面二维水沙模型计算得到的流速分布与河床高程的模拟值与试验值基本吻合,表明采用数值模拟探究心滩绕流近壁面流场水力特性是可行的.本研究将为揭示黄河下游典型冲积河段心滩形态特征调整过程的动力学机理提供理论基础.The typical mid-channel bar near the Mayugou cross-section in the Lower Yellow River was taken as the research object,the hydraulic characteristics of the flow field near the wall of the mid-channel,such as the flow pattern,the riverbed elevation,the sediment carrying capacity and the bed surface resistance were described by model experiment and numerical simulation under different flow rate and water depth conditions,and the correctness of the flow velocity and the riverbed elevation calculated by the planar two-dimensional water-sediment model was verified.The results show that the flow velocity of the cross-section in the diverting area decreases under the influence of the mid-channel bar head,and the maximum flow velocity all appears in the branch.Under the influence of the mid-channel bar tail,the boundary layer separation occurs in the cross-section of the confluence area,and the flow velocity in the center of the flume reaches the minimum,and then the flow velocity gradually reaches the maximum and tends to average.The simulated results of the flow velocity and the riverbed elevation calculated by the planar two-dimensional water-sediment model are basically consistent with the experimental results,which indicates that it is feasible to use the numerical simulation method to explore the hydraulic characteristics of the flow field near the wall of the mid-channel bar.This paper will provide theoretical basis and technical support for revealing the dynamic mechanism of the adjustment process of the mid-channel bar morphological characteristics in the typical alluvial reach of the Lower Yellow River.

关 键 词：心滩绕流 水力特性 数值模拟 黄河下游 水沙模型 

分 类 号：S277.9[农业科学—农业水土工程]