二维加糙明渠流理论床面的确定方法  

Determination of zero-plane displacement in two-dimensional roughened open channel flow

作　　者：毛冉冉 程年生 卢叶盛 MAO Ran-ran;CHENG Nian-sheng;LU Ye-sheng(Ocean College,Zhejiang University,Zhoushan 316021,China;The Engineering Research Center of Oceanic Sensing Technologyand Equipment,Ministryof Education,Zhoushan 316021,China)

机构地区：[1]浙江大学海洋学院,浙江舟山316021 [2]海洋感知技术与装备教育部工程研究中心,浙江舟山316021

出　　处：《泥沙研究》2022年第6期9-14,共6页Journal of Sediment Research

基　　金：国家自然科学基金项目(51979242)。

摘　　要：确定粗糙明渠流的理论床面对分析流速分布的特性具有学术价值。针对二维半圆柱体加糙床面,通过改变水深、流量和粗糙元间距,开展了一系列水槽实验研究。运用粒子图像测速技术进行流场测量,首先获取经时间和空间平均后的流速垂线分布资料,然后分析了理论床面位移随雷诺数等多种水力参数的变化关系。为能综合反映水深、粗糙元高度及其间距等参数的影响,应用水力半径概念,提出了新的特征长度。分析结果表明:相较于其他参数,该特征长度可以更好地描述理论床面位移的变化。A series of laboratory experiments were carried out in an open channel with a semi-cylinder roughened bed.The velocity field was measured by a particle image velocimetry technique(PIV).The data were further used to compute the temporal and spatial averaged velocity profiles.The variations of zero-plane displacement with Reynolds number and other hydraulic parameters were analyzed.To consider the combined influence of flow depth,roughness height and roughness spacing,the concept of hydraulic radius was applied to develop a new characteristic length.The results show that the characteristic length is better than other parameters in the description of the variation of the zero-plane displacement.

关 键 词：明渠 紊流 二维粗糙元 水力半径 理论床面 

分 类 号：TV131[水利工程—水力学及河流动力学]