非均匀散粒粗糙床面明渠紊流特性研究  

Characterization of Turbulent Flow in Open Channel with Non-uniform Bulk Rough Bed

作　　者：徐翔宇 钟亮[2] 李国际 阎鑫铭 XU Xiang-yu;ZHONG Liang;LI Guo-ji;YAN Xin-ming(National Engineering Research Center for Inland Waterway Regulation,Chongqing Jiaotong University,Chongqing 400074,China;Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education,Chongqing Jiaotong University,Chongqing)

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]重庆交通大学水利水运工程教育部重点实验室,重庆400074

出　　处：《中国农村水利水电》2024年第3期137-142,共6页China Rural Water and Hydropower

基　　金：国家自然科学基金资助项目(51509026)。

摘　　要：为揭示非均匀散粒粗糙床面明渠紊流特性,采用d_1=1.0 cm、d_2=1.5 cm的正方体散粒制成粗糙床面开展PIV水槽明渠紊流试验,探讨了紊动强度、速度高阶矩、雷诺应力和紊动能的分布规律。结果表明:(1)粒间区中部,邻近剖面颗粒的绕流作用使紊动强度发生明显变化。(2)速度高阶矩纵向偏度系数S_(u')与垂向偏度系数S_(v')的分布特性揭示在近床处主要发生扫掠事件,而颗粒顶部以上区域喷射事件占主导。(3)平均雷诺应力R_(mean)在粒间区沿程先增大再减小,在颗粒区先减小后增大。(4)紊动能呈条带状分布,在河床底部和水面受到的抑制使得整体紊动能从床面开始增大,在颗粒顶部附近达到最大之后开始减小。In In order to reveal the turbulence characteristics of open channel with rough bed of non-uniform bulk particles,this paper uses the rough bed surface made of cubic particles with d1=1.0 cm and d2=1.5 cm to carry out the turbulence test of open channel in PIV flume to investigate the distribution of turbulence intensity,higher-order moments of velocity,Reynolds stress and turbulence kinetic energy.The results show that:①In the middle of the intergranular zone,the turbulence intensity changes significantly due to the bypassing effect of neighboring profiled particles.②The distribution properties of the longitudinal skewness coefficient Su′and the vertical skewness coefficient Sv′of the velocity high-order moments reveal that sweeping events predominate near the bed,while ejections dominate in the region above the top of the particles.③The mean Reynolds stress Rmean increases and then decreases along the intergranular region,and decreases and then increases in the granular region.④The turbulent kinetic energy is distributed in bands,and the suppression at the bottom of the riverbed and at the water surface causes the overall turbulent kinetic energy to increase from the bed surface and to decrease after reaching a maximum near the top of the particles.

关 键 词：非均匀散粒粗糙 明渠紊流 紊动强度 速度高阶矩 雷诺应力 紊动能 

分 类 号：TV143.5[水利工程—水力学及河流动力学]