排灌机械工程学报2019，Vol.37Issue(3)：216-223,8.DOI:10.3969/j.issn.1674-8530.18.0084
掺气坎组合首级台阶对阶梯溢流坝面的影响
Effect of combination of aerated hurdle and the first stage step on stepped spillway surface
摘要
Abstract
In order to avoid cavitation damage on surfaces of the first few steps of a stairway spillway, an aerated hurdle was added to the design of stairway spillway to form a pre-mixed culvert spillway. The transition step shape with improved hydraulic characteristics was sought in terms of cavity length, water line, negative pressure, time-averaged pressure on stilling bottom, energy dissipation and so on by changing reservoir flow through experiments on a series of hydraulic models. In these experiments, the first step in the transition step was fell by 0°, 5°, 10° and 15°, and the pre-aeration angle had 8°, 10°two values, the joint energy dissipators with Y-shaped flaring gate piers, stepped spillway and stilling pool were built based on eight combinations of these parameters respectively. The results show that the aerated cavity increases with increasing pre-aerator and first stage angle, the higher the water jet, the larger the space separating from the dam surface and the longer the cavity length. The length of cavity in working condition 2 is longer than in working condition 1; the absolute value of the maximum negative pressure decreases with increasing aerator and first step slope. The pressure and water line are not changed much, and the energy dissipation rate increases. Thus, the fifth case with 10° aerated hurdle angle and 0° first stage step slope is the best combination in eight experimental combinations.关键词
Y型宽尾墩/阶梯溢流坝/首级台阶/掺气坎Key words
Y-shape flaring gate pier/stepped spillway/first step/aerated hurdle分类
建筑与水利引用本文复制引用
张勤,杨具瑞,汤建青,叶小胜,郭莹莹..掺气坎组合首级台阶对阶梯溢流坝面的影响[J].排灌机械工程学报,2019,37(3):216-223,8.基金项目
国家自然科学基金资助项目(51569010) （51569010）
