某人工弯道式渠首分层取水结构段模型试验研究

以某人工弯道式渠首改造工程为背景，在人工弯道式渠首泄洪闸上游设置分层取水结构段，用水平隔板将水流分开，上层引水、下层冲沙。研究了分层取水建筑物的水力特性，解决了人工弯道式渠首建筑物的引水和排沙问题。为确定该分层取水结构段的结构设计合理性，采用水工模型试验方法，分别对不冲沙和泄洪闸单孔冲沙两种试验工况，观察分析了分层取水结构段的水流流态，并测量各个断面的水深、流速、引水流量和冲沙流量等水力要素。结果表明:该分层取水结构段能达到设计的引水流量要求；且单孔冲沙时，闸门开度越大，冲沙效果越好。该试验结果可为类似的多泥沙河流的综合整治工作提供借鉴。

Model Experiment of Layered Water-taking Structure in a Project of Headwork with Artificial Bend

Taking a renovation project of headwork with artificial bend as the study project ,a layered water-taking struc-ture was designed in the upstream of the floodgates of the project of headwork ,which is divided into two parts by a sus-pension slab .The upper layer is used for water diversion and the lower layer is used for sediment washing .The hydraulic characteristics of the layered water-taking structure have been analyzed ,and at the same time ,the water diversion prob-lem and sediment problem for the project of headwork can also be solved .The model experiment was used to confirm the rationality of the layered water-taking structure .The experiment includes two working conditions ,one condition is that all the water flows into the headwork with bend ,the other is that some water flows into the headwork with bend and the other is used for sediment washing .Only one of the three floodgates was opened in the second working condition .In the experi-ment ,the hydraulic elements include water depth ,flow velocity ,and the discharge for water diversion and for sediment washing were observed and recorded .The conclusion is that the layered water-taking structure can satisfy the design re-quirements of the water diversion ,and for the second condition ,the larger the gate opening ,the better its washing sedi-ment efficiency .This research could be used for reference in the comprehensive treatment for similar structures .