窄缝挑坎在水利工程中应用广泛,但尚无成熟的设计方法,工程设计中窄缝主要参照类似工程初拟体型,并经模型试验优化后最终定型。但模型试验存在耗时长、费用高、常规仪器测量精度较低的不足。采用RNG k-ε紊流模型,利用Flow 3D独特的FAVOR网格技术,对小湾水电站泄洪洞窄缝挑坎进行三维数值模拟研究。模拟结果表明窄缝挑坎内水深、水舌形态、水舌前后入水点、水舌最高点及起跳角度等计算结果与模型试验、原型观测值基本一致。表明Flow 3D数值模拟研究方法可作为窄缝挑坎设计的一种方法,并可节省时间和工程费用,优势显著。

Although slip-type flip bucket is widely used in hydraulic projects, there is no mature method to design it. The bucket type is designed preliminarily according to similar projects, and is optimized through model test. However, model test features with long time, high cost,and low accuracy of conventional instruments. In this article, three-dimensional numerical simulation is carried out on the slip-type flip bucket at the flood discharging tunnel of Xiaowan hydropower station in association with RNG k-ε turbulence model and FAVOR technology of Flow 3D. The computation results of some main hydraulic parameters inclusive of water depth, water jet shape, point of jet entering water in the downstream and upstream, peak height of water jet, and angle of water jet are in accordance with model test and prototype observation. Flow 3D could save time and cost in designing slip-type flip bucket.