高差动坎在拱坝泄洪表孔中的应用研究

针对中小型拱坝表孔大流量泄洪时存在的向心集中问题,结合某工程泄洪表孔消能工,采用数值模拟与模型试验相结合的方法对其不同体型的方案进行了对比分析。结果表明,表孔大流量泄洪时,设置高差动坎体型与窄缝式及低差动式挑坎相比,水舌纵向拉开更加明显,并伴有一定的横向扩散,水舌落点分布均匀,对河床形成的冲击压力较小且分散,消能效果较为显著。此外,其空蚀破坏可能性也不大,可见高差动坎体型总体安全、合理。

Application of High Differential Flip Bucket in Surface Spillways on Arch Dam

Aiming at the concentric concentration problem caused by large discharges in crest outlet of middle or small arch dam, combined with numerical simulation and model test was used to analyze the scheme of different structures by combining the energy dissipator of flood-discharge crest outlet for a certain project. The results show that when the flood discharge is large, the structure of the high-differential flip bucket is more superior to the narrow-slot type and the low-differential type. In this case, water tongue longitudinal stretch more obviously, accompanied by a certain degree of lateral diffusion; energy and impact pressure of water flow on the river bed is light and dispersed because of the uniform distribution of water placement. In addition, the possibility of cavitation damage is not obvious. Thus, it indicates that the high-differential flip bucket is safe and reasonable.