滕晓敏 陈威 杨金孟 张庆华 张靖

摘要：为了探索透水斜槛对溢洪道泄槽弯道水流的改善效果，在弯道底板布置了5道斜角45°透水率分别为279%、379%、495%的透水斜槛进行了模型试验。利用试验结果，计算了弯道横断面水面均匀度及提高率、凹凸岸水面差及减少率等指标，以此分析不同透水率斜槛、不同流量条件下弯道段水流的改善效果影响。结果表明：弯道设置透水斜槛后能够改善弯道水流，提高弯道水流均匀度，降低凹凸岸水面差；透水率对水流改善效果有影响，在相同流量情况下，透水率越小，斜槛对水流改善的效果越好；斜槛改善水流的效果随流量变化，流量越小，改善效果越明显。但就弯道横断面水面均匀度改善效果而言，不同透水率、不同流量之间相差不大。

关键词：溢洪道；弯道水流；透水斜槛；水面均匀度；水面差

中图分类号：TV1 文献标志码：A 文章编号：

16721683（2018）05017108

Model test of flow improvement effect of the permeable oblique sill on the bend in spillway chute

TENG Xiaomin，CHEN Wei，YANG Jinmeng，ZHANG Qinghua，ZHANG Jing

（

College of Water Conservancy and Civil Engineering，Shandong Agricultural University，Taian 271018，China）

Abstract：

In order to explore the flow improvement effect of permeable oblique sill on the spillway chute bend，we carried out a model test of five permeable oblique sills （laid at an angle of 45°） with a permeable rate of 279%，379% and 495%.Based on the test results，we calculated the water surface evenness and the corresponding improvement rate，the water surface difference between concave bank and convex bank and the corresponding decrease rate，so as to analyze the effect of different permeable rates of the sill and different flow rates on improving the flow of the bend.The results were as follows.Firstly，the permeable oblique sill set at the bend could strongly improve the bend flow，increase water surface evenness at the bend，and decrease water surface difference.Secondly，permeable rate could affect the flow improvement effect.Under the same flow rate，the smaller the permeable rate，the better the effect of the sill on flow improvement.Thirdly，the effect of the sill on flow improvement would vary with the flow rate；the effect was more obvious when the flow rate was low.Regarding the improvement effect on the water surface evenness at the bend，the different permeable rates or flow rates did not make much difference.

Key words：

spillway；bend flow；permeable sill；water surface evenness；water surface difference

溢洪道泄槽段的特點是上下游高差大、坡度陡、水流呈急流状态。因此，工程设计中要求泄槽尽量顺直、等宽[1]，以避免和减少水流冲击波对水流的扰动。但在实际工程中，由于受地形、地质等的限制，许多工程泄槽段需要设置弯道。受弯道横向环流的影响，弯道水流流态恶化，弯道内产生横向冲击波，致使弯道凹侧水深加大，凸侧水深减少，从而使凹凸岸产生较大的水面差，导致泄槽横向水流不均匀，给下游消能带来不利的影响[23]。因此，当溢洪道泄槽出现弯道段，且弯道轴线半径较小时必须采取工程措施，以改善溢洪道弯道水流条件。……