射流形状对水垫塘底板冲击动压特性的影响  

Effects of jet flow with different aspect ratios on the impact pressure in the plunge pool bottom

作　　者：卢艳娜 李龙国[1] 李乃稳[1,2] 刘超[1] 邓军[2] 

机构地区：[1]四川大学水利水电学院,成都610065 [2]四川大学水力学与山区河流开发保护国家重点实验室,成都610065

出　　处：《南水北调与水利科技》2014年第6期89-92,共4页South-to-North Water Transfers and Water Science & Technology

基　　金：国家自然科学基金青年科学基金项目(50909067;51009102;51179113);新世纪优秀人才支持计划(2011SCU-NCET-10-0589)

摘　　要：高坝工程坝身泄洪水流对下游水垫塘底板的冲击动压是水垫塘底板失稳破坏的重要因素。通过物理模型试验的方法详细分析了斜向淹没冲击射流形状(射流长度与宽度之比)对水垫塘底板的冲击动压分布特性影响,结果表明:随着射流长宽比的增加,射流入水形状由宽扁形横向扩散入水转变为窄长形纵向扩散入水,水垫塘底板上的冲击动压和脉动压强先增大后减小。同时,上游水位及下游水垫深度对冲击动压值及分布也存在较大影响,冲击动压值随上游水位增加而增大,随下游水深增加而减小。The impact pressure on the plunge pool bottom caused by the flow discharge of high dam is a key factor to lead to the instability of the plunge pool.In this paper,the effects of the submerged jet flow shape （aspect ratio of jet flow length and width） on the impact pressure distribution in the plunge pool bottom were investigated based on the physical model tests.The results showed that with the increasing of aspect ratio,the shape of jet flow varies from the wide-flat shape with horizontal diffusion to the long-narrow shape with vertical diffusion,and the impact pressure and fluctuating pressure on the plunge pool bottom increase first and then decrease.In addition,the upstream water level and downstream water depth have great effects on the impact pressure in the plunge pool bottom,and the fluctuating pressure increases with the increasing of upstream water level but decreases with the increasing of downstream water depth.

关 键 词：冲击射流 射流形状 压力特性 

分 类 号：TV135.2[水利工程—水力学及河流动力学]