基于最小拉沙弃水量的小浪底枢纽排沙洞闸门不同相对开度方案试验研究

Experimental study of different gate relative opening scheme based on the minimum water required for desilting tunnel of Xiaolangdi Multipurpose Dam Project

作为黄河干流上调节泥沙的控制性工程,小浪底水库对于黄河下游的防洪减淤起着十分重要的作用。目前,随着黄河水量的日益减少,以较少的水量排出较多的泥沙已成为枢纽研究的重点。本文以小浪底进水塔为研究对象,建立坝前库区正态浑水动床实体模型。在对模型的相似性进行验证的基础上,选取坝前特征水位210 m为控制条件,对进水塔前187.0 m淤沙高程进行排沙洞闸门不同相对开度方案试验研究。通过对试验结果分析对比,提出了在1号、2号排沙洞工作闸门取相对开度0.15,3号排沙洞工作闸门取相对开度0.18进行泄流拉沙时,在满足预期拉沙效果,保证发电效益不显著降低的前提下,所需拉沙弃水量较小的结论。

As the control project of regulating the sediment of Yellow River,Xiaolangdi reservoir plays a very impor⁃tant role for the flood prevention and sedimentation reduction in the lower reaches of the Yellow River.The flow of Yellow River is decreasing at present,so flushing more sediment with less water becomes the focus of study.With the intake tower of Xiaolangdi as the object of research,a normal muddy water movable-bed physical model of reser⁃voir area was established.The similarity of model was verified,based on which the upstream characteristic level of 210m was chosen as the control condition,tests were conducted to study different gate relative opening scheme for the desilting tunnel at sedimentation elevation of 187.0m.The results of test were analyzed,based on which it is con⁃cluded when the gate relative opening of No.1 and No.2 desilting tunnels is 0.15 and the opening of No.3 desilting tunnel is 0.18,the expected sediment flushing effect is satisfied with the minimum amount of water and without sig⁃nificant decrease of power generation benefits.