颗粒非均匀性对推移质输移影响的试验研究  

Experimental study on the impact of the non-uniform characteristics of the particles on the bed load transport

作　　者：刘明潇[1,2] 王鹏涛[2] 孙东坡[2] 高昂[2] 

机构地区：[1]西安理工大学水利水电学院,陕西西安710048 [2]华北水利水电大学水利学院,河南郑州450045

出　　处：《泥沙研究》2014年第6期30-35,共6页Journal of Sediment Research

基　　金：国家自然科学基金重点资助项目(51039004);河南省创新型科技人才队伍建设工程

摘　　要：非均匀推移质运动是一个复杂的物理过程,输移量的确定、关键影响因子的辨识、内在作用机理的把握等基本规律的研究尚不充分。基于此,本文开展了系列精细水槽试验,结合高速摄像、图像识别技术,获取了非均匀推移质输移、颗粒拣选度变化等过程的动态监测数据。引入非均匀泥沙粗细比η,反映床面粗糙度、黏性底层与床面泥沙特性在内的综合水流强度函数Ψb,特征傅氏数Frb等参数,采用量纲分析与数值拟合相结合的方式,研究了不同粗细比的非均匀推移质输移规律。分析表明颗粒的非均匀性是影响推移质输移的关键因子,对粗颗粒输移量及全沙输移强度影响至关重要;推移质输移率与颗粒粗细比、水流强度呈紧密依存关系。Non-uniform bed load transport is a complex physical process, and study on some basic problems, such as the calculation of the transport rate, the identification of the key factors and the grasp of the internal mechanism are yet inadequate. Based on current status, series of flume experiment have been conducted, and the real-time monitoring data, recording the processes of the transport of the non-uniform bed load and the changes of the selection coefficient of the particles, have been acquired credibly combined with the high-speed video and technology of the image recognition. Parameters of 77 （mass contrast of the coarse sand and fine sand）, qt （comprehensive function of the flow intensity which reflected the bed roughness, viscous sublayer thickness, characteristic of the bed sediment）, Frb（characteristic Froude number） are introduced in the pa- per. Transport laws of the non-uniform sediment with different thickness ratios of the coarse sand and fine sand have been studied by the method combined with dimension analysis and numerical fitting. Analysis shows that the non-uniformity of the particles, which is one of the key influence factors of the bed load transport, has an crucial effect on the transport quantity of the coarse particle and the transport intensity of the total sediment ; the transport rate of the bed load has an interdependent relationship with the thickness ratios of the particles and the flow intensity.

关 键 词：推移质 颗粒非均匀度 综合水流强度函数 图像识别 近壁水流结构 

分 类 号：TV147[水利工程—水力学及河流动力学]