多级复式断面河道植被水流特性试验研究  

Experimental study on the flow characteristics of multi-stage compound channel with vegetation on its floodplains

作　　者：王雯[1] 槐文信[1] 曾玉红[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《华中科技大学学报（自然科学版）》2013年第10期128-132,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51079102);高等学校博士学科点专项科研基金资助项目(20100141110028);武汉市青年晨光计划资助项目(201050231059)

摘　　要：在均匀流条件下对多级复式断面河道中边滩上无植被及有植被情况下的水流特性进行了试验研究.在复式断面渠道的两级阶地上布设钢筋模拟刚性植被,采用三维多普勒超声流速仪(ADV)对三维流场进行了测量,并与无植被条件下的流速场进行了对比试验.根据实测结果,对横断面上的流速等值线图、纵向流速的垂线分布、水深平均纵向流速的横向分布,二次流分布及紊动能分布进行了分析.结果表明:植被的存在,加大了边滩的阻力,促使河道内主流速加速回归河道主槽,二次流主要发生在一级阶地处,最大紊动能亦出现在此处.与无植被多级复式断面比较而言,对数流速定律在二次流及强紊动的影响下,适用范围显著减小.Experimental study was conducted in a two-stage compound channel with and without vege- tation on its floodplains under uniform flow. Steel bars were used to simulate rigid vegetation on the terraces, and 3D acoustic doppler velocimetry （ADV） was adopted to measure the flow velocities and the results were compared with that without artificial vegetation on the terraces. With the measured three-dimensional velocity, the velocity contour maps, vertical distribution of longitudinal velocity, lateral distribution of depth-averaged velocity, the secondary flow and turbulent energy distribution were analyzed. The results show that the vegetation on the terraces increases the friction and as a re- suit, the main streamwise velocity is regulated to the main channel quickly, and secondary current is mainly generated near the first stage terrace. The maximum turbulent energy also appears at the area. Compared with the flow without vegetation, the applicability of the logarithmic law is narrowed.

关 键 词：明渠流动 植被 流速分布 复式河道 二次流 紊动能 

分 类 号：TV91[水利工程—水利水电工程]