中文摘要：

采用k-e紊流模型，并结合VOF方法，对锦屏一级水电站泄洪洞明流段的两种布置方案进行了数值计算。计算中对壁面粗糙度的合理取值范围进行了分析讨论，并就其对计算结果的影响进行了定性分析。得到了按正常泄量泄洪时“龙落尾”和“龙抬头”泄洪洞内压力分布、空化数分布、沿程水深及平均动能的变化。通过比较，认为“龙落尾”式布置方式缩短了需要掺气保护的洞段长度，可降低工程空化空蚀破坏的风险程度；而“龙抬头”式布置方式的防空蚀性能稍好，出口水流的能量也小，对下游河道的消能防冲有利。

英文摘要：

Three-dimensional numerical simulation on free surface flow of spillway tunnel in Jinping hydro project is performed. The k-ε model is adopted to describe the turbulence flow and VOF method is applied to track the free surface of the flow. The rational range of the equivalent roughness value and its effects on numerical results for different spillway are analyzed and discussed. The pressure distribution, water flow depth, cavitation number, sectional averaged velocity and water head variation are calculated for both two types of spillway tunnels which are inclined the elbow part of tunnel is near the intake and the other part is near the outlet. The result shows that the latter of two types of spillway tunnels has a high anti-risk capability in the view point of risk analysis, while the former has a better performance for cavitation mitigation, and is helpful to the energy dissipation and avoiding scour of the downstream riverbed.