岷江张坎航电枢纽船闸引航道通航水流条件优化

Optimization of navigable flow conditions for approach channel of Zhangkan Navigation-power Junction ship lock on Minjiang River

拟建岷江张坎航电枢纽位于S形弯曲河道上,船闸下游口门区在弯道和复杂河床地形的影响下,水流条件难以满足通航标准要求。针对该工程面临的水流条件问题,采用平面二维水流数值模拟方法,在充分利用下游口门区原始地形的基础上,通过改变引航道边墙堤头形式、延长引航道边墙并向左岸偏转、增设导流墩等措施提出3个优化方案。结果表明:采用R=125 m的弧形引航道堤头,外加1个导流墩的布置方案,不仅能有效降低口门区横流、回流流速,亦能通过导流墩与引航道边墙的间隙引流破坏河道连接段回流的形成条件,从而改善在大流量下因弧形堤头引起连接段明显的回流现象,优化后的下游口门区及连接段通航水流条件满足规范要求,研究成果可为类似工程提供借鉴和参考。

The proposed Zhangkan Navigation-power junction in the Minjiang River is located on the S-shaped curved channel.The flow conditions in the downstream entrance area of the ship lock are difficult to meet the navigational standards due to the influence of the curved channel and complex riverbed topography.In view of the flow conditions of the project,a two-dimensional numerical simulation method of water flow is adopted.On the basis of fully utilizing the original topography of the downstream entrance area,three optimization schemes are proposed by changing the shape of the guidance wall of the approach channel,extending the guidance wall of the approach channel and deflecting to the left bank,and adding diversion piers.The results show that the arrangement scheme of adopting R=125 m curved guidance wall and one diversion pier can not only effectively reduce the cross-flow and back-flow velocity in the entrance area,but also destroy the formation conditions of back-flow in the connecting area through the gap between the diversion pier and the guidance wall,thus improving the condition of back-flow caused by the curved guidance wall in the connecting area under the high flow rate.The optimized downstream flow conditions in the entrance area and the connecting area meet the navigational standards,and the research results can provide references for similar projects.