摘要
近年来,阶梯泄槽工作水头存在大幅增长趋势,大落差多级阶梯溢洪道逐渐得到广泛应用。本文对三个50～70m落差水利工程的阶梯溢洪道进行了实验研究,在单宽流量q=30m2/s情况下对阶梯水流流场进行了三维数值模拟。实验与数模结果均反映出,大落差多级阶梯泄槽存在一个过去未曾提出的规律:通过沿程阶梯旋滚消能,总水头线在下游段与阶梯外包络线平行,断面比能保持不变,亦即阶梯水流的稳定平衡态,在此状态下,水流减少的位能将全部被耗散掉,平均速度基本不变,此规律为今后阶梯泄槽应用水头的进一步增大,提供了重要依据。
In recent years,there has been a great growth trend in the working head of stepped chutes and high-head stepped spillways with mass steps have been used widely.In this study,a physical hydraulic model test was conducted to evaluate the performance of three stepped spillways with a head range of 50~70m,and the three-dimensional field of stepped flow with a unit discharge q=30m2/s was simulated.Through analysis of the experimental and calculated results,we found out that these stepped chutes with mass steps follow a law that in their downstream part,the energy dissipation by their multiple steps leads to a gross head line parallel to the envelope curve of these steps and a specific energy that remains unchanged along the flow.This means a stable equilibrium of the skimming flow over the chutes,i.e.all the decrease in potential energy is dissipated so that the mean velocity remains constant.This law was not reported in the past and it will be important to stepped chute design for further increase in working head.
出处
《水力发电学报》
EI
CSCD
北大核心
2013年第2期190-194,共5页
Journal of Hydroelectric Engineering
基金
国家自然科学基金(51209155
51109149)
教育部博士点基金(20110181120093)
关键词
水力学
稳定平衡态
实验研究
数值模拟
阶梯泄槽
断面比能
hydraulics
stable equilibrium
physical model
numerical simulation
stepped chute
specific energy
