盘龙寺拦河闸枢纽引航道模型试验研究

盘龙寺拦河闸枢纽工程拟在右岸兴建引航道,需通过水工模型试验研究分析盘龙寺拦河闸枢纽工程通航建筑物的布置方式及上下游引航道口门区的通航水流条件。试验结果显示:在5年一遇洪水条件下,上游航道口门区纵向流速最大为1.33 m/s,横向流速最大为0.28 m/s,稍微超标;原方案下游引航道口门区在四种试验条件下均有不同程度超过规范要求,原因在于下游引航道口门区受河道弯道影响,航道中心线与河道主流存在夹角引起汇流不平稳。为了通航安全需在上游引航道局部段设置引航线,控制最大通航流量应设置为4 900 m~3/s。同时,提出了下游引航道口门区优化布置方案,改变下游引航道外侧导墙布置长度,将原来的末端40 m直线型导墙改为半径为50 m,偏角为16°,偏向河中央的弧线型导墙。改进后的方案有效地改善了下游引航道口门区附近的通航水流条件,流速符合内河航道通航规范要求。

Model experimental study on approach channel for Panlongsi Sluice Project

As an approach tunnel is planned to be constructed on the right bank of Panlong Sluice Project， the layout modes andthe navigation flow conditions at the entrance areas of both the upstream approach channel and the downstream approach channelof the navigation structure for Panlongsi Sluice Project are mainly studied herein through the relevant hydraulic model experiment.The experiment result shows that under the condition of the flood with the return period of five years， the maximum longitudinalflow velocity is 1. 33 m / s and the maximum transverse flow velocity is 0. 28 m / s in the entrance area of the upstream approachchannel， which are slightly exceed the relevant standards， while the all flow velocities in the entrance area of the downstream ap-proach channel in the original scheme under four experiment conditions exceed the requirement of the relevant specification some-what， for which the causation comes from the impact of the bended river channel on the entrance area of the downstream approachchannel， i. e. an intersection angle is there between the central line of the navigation channel and the mainstream of the river， which makes the converging flow therein unstable. In order to ensure the navigation safety， an approach line must be set for thelocal section of the upstream approach channel， while the maximum control navigation flow rate of 4 900 m3/ s must be set aswell. Moreover， the optimized layout scheme for the downstream approach channel is proposed， i. e. the layout length of the out-side guide-wall of the downstream approach channel is modified from the straight guide-wall with 40 m-long end into an arc shaped guide wall， that is deflected to the central line of the river， with the radius of 50m and deflected angle of 16°. The modi-fied scheme effectively improves the condition of the navigation flow near the entrance of the downstream approach channel andthe flow velocity accords with the specified navigation requirement for the inland water way.