明渠湍流涡运动尺度分布特性  

Distribution of motion scales of vortices in turbulent open channel flow

作　　者：张鹏[1,2] 杨胜发[1,2] 胡江[1,2] 陈阳[1,2] 幸韵[1,2] 

机构地区：[1]重庆交通大学国家内河航道整治工程技术研究中心,重庆400074 [2]重庆交通大学河海学院,重庆400074

出　　处：《水科学进展》2015年第1期91-98,共8页Advances in Water Science

基　　金："十二五"国家科技支撑计划资助项目(2012BAB05B03);交通运输部应用基础研究项目(2014329814310)~~

摘　　要：为了解明渠湍流涡运动尺度沿水深的分布特征,使用高精度粒子图像测速法水槽试验系统测量充分发展的明渠湍流,利用改进后的功率谱分析方法,对明渠湍流涡运动尺度沿水深分布、上升流、下扫流和平均涡量等进行了分析。结果表明:明渠湍流涡运动尺度大小沿水深增加呈先增大后减小;沿水深增加下扫流比上升流更容易发生;各自水深的顺向涡涡量大于逆向涡涡量,在近壁区平均涡量最大;明渠湍流近壁区产生涡量大、尺度小的涡结构,沿水深增加,涡尺度发展变大,但受水面区下扫流抑制,涡尺度又变小。To understand the distribution of motion scales of vortices in turbulent open channel flow along water depth. A flume experiment system based on high-resolution particle image velocimetry（ PIV） was applied to measure fully developed turbulent open channel flow. Meanwhile,the distribution of motion scale of vortices in turbulent open channel flow along water depth,upwelling,sweep down flow and average swirling strength etc. were analyzed using improved power spectrum estimation. The results indicate that the motion scale of vortices in turbulent open channel flow first increases and then decreases along the water depth. The sweep down flow is more prone than upwelling along the water depth. The swirling strength of prograde vortex is larger than that of ret-rograde vortex at respective water depth. The swirling strength of near-wall region is the greatest. Vortices featured by great swirling strength and small scale occur in the near-wall region,then,the vortex scale becomes greater along the water depth,while it decreases under the inhibitory effect of sweep down flow in surface area.

关 键 词：明渠 湍流 涡尺度 功率谱 上升流 下扫流 

分 类 号：TV131[水利工程—水力学及河流动力学]