突扩突跌掺气射流对泄洪洞侧墙水力特性的影响  

Effect of aerated jet on hydraulic characteristics of spillway tunnel side-wall with abrupt lateral expansion and bottom offset aerator

作　　者：马旭东[1] 戴光清[1] 杨庆[1] 李国敬[1] 

机构地区：[1]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：《水力发电学报》2012年第3期142-147,共6页Journal of Hydroelectric Engineering

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

摘　　要：采用VOF和RNGk-ε紊流模型模拟突扩突跌型中闸室出口高速三维掺气射流。突扩掺气射流冲击壁面的反射作用使近壁流动具有强烈的各向异性,反射流向洞顶扩散形成水翅,突扩宽度和闸室出口水流佛汝德数是影响水翅的主要因素。出闸射流碰撞泄洪洞底板后,反射形成侧壁压力中心,其周围具有较大的压力梯度,容易诱发剪切空化。This article presents a simulation of a high-speed three-dimensional aerated jet from a middle-gate chamber outlet created by an aerator with abrupt lateral expansion and bottom offset using a mathematical model of RNG k-ε two-equation formulation and volume of fluid method for free surface calculation.Impact of high-speed aerated jet against side wall and its reflection produce a near-wall flow of strong anisotropy and cause a large water wing generated on the wall.The expansion angle and Froude number of the gate chamber outlet are the key factors influencing the strength of water wing.Downstream the impact of jet on the tunnel bottom,a central area on side-wall with higher pressure is formed under reflection to the aerated jet＇s impact.The huge pressure gradient in this small central area often becomes a cause of shear cavitation.

关 键 词：水力学 突扩突跌 掺气射流 侧墙 空化 水翅 

分 类 号：TV131.34[水利工程—水力学及河流动力学]