泄水建筑物反弧末端掺气坎的布置研究  

Study on Aerator Arrangement of Concave Reach Bottom of Discharge Structures

作　　者：王海云[1] 戴光清[2] 刘超[2] 杨庆[2] 马旭东[2] 

机构地区：[1]四川大唐国际甘孜水电开发有限公司,四川康定626001 [2]四川大学水力学与山区河流开发保护国家重点实验室,四川成都610065

出　　处：《四川大学学报（工程科学版）》2010年第2期9-14,共6页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(50779041);教育部博士点基金(20060610039)资助项目

摘　　要：在泄水建筑物中,为了减免在高速水流作用下过流面发生空蚀破坏,反弧段末端常常设置掺气坎。工程实践和科研表明,当掺气坎后为小底坡时,空腔内容易出现回水壅堵现象,减小了有效空腔长度,掺气效果不理想。采用数值模拟、模型试验的方法,对反弧末端掺气坎的布置进行了探讨得出:在泄洪洞反弧段末端设置底部掺气坎时,反弧段后附加离心力对底部空腔长度有显著影响。在反弧末段增加水平延长段后,反弧段下切点之后附加离心力具有过渡性质,随着附加离心力的减小,掺气坎后空腔长度有明显增加区间;水平延长段长度与反弧弧长的比在0.16范围内为空腔长度明显增加区间,在此区间内掺气坎后水流的水力特性得到了改善。In the discharge structure,in order to prevent flowing interface from being destroyed by cavitation under high speed velocity,aerator was introduced to concave reach bottom.Engineering practice and scientific research showed that backwater appeared in the cavity to reduce the effective cavity length and the aerated result was not good under the condition of a small slope after aerator.Through numerical simulation and model test,aerator arrangement was studied.The results showed that while adopting aerator on the bottom of concave section,adding the centrifugal would remarkably influence on the length of bottom cavity;Introducing lengthen section on the bottom of concave reach,the additional centrifugal force had transition nature after the tangential point;With the reducing of adding centrifugal,the length of bottom cavity obviously increased;When the length ratio of lengthen section and concave lengthwas in 0.16,the bottom cavity length obviously increased,and the hydraulic characteristic got certain improvement.

关 键 词：泄水建筑物 反弧末端 掺气坎 布置 

分 类 号：TV651[水利工程—水利水电工程]