双层刚性植被明渠水流特性实验研究

Characteristic study of open-channel flow through double layer rigid vegetation

基于粒子图像测速(PIV)技术对双层刚性植被水流进行了水槽实验,分析了植被在不同流量、水深以及不同植被排布方式下对水流的影响,研究了双层刚性植被水流的纵向流速、垂向流速和紊动强度等水力特性.实验结果表明:当水深和流量相同时,线性排列的植被对水流的抑制效应强于交错排列的植被;当植被排布方式相同,流量和水深在一定范围内增大时,植被对水流的抑制效应也随之增大;双层植被的存在,使水流的流动结构及紊动特性变得更为复杂,在植被层顶部附近物理量变化最为显著.

Based on the laboratory flume experiments with particle image velocimetry（PIV）,the profile of longitudinal velocity,vertical velocity and turbulence intensity of open-channel through double layer rigid vegetation were presented in the paper.The influence of water depth,flux and vegetation towel arrangement on flow was analyzed.The results suggest that,in the same water depth,the vegetation resistance of the staggered configurations is smaller than the linear configurations.Meanwhile,in same towel arrangements,the vegetation resistance increases when the water depth rises within limits.Owing to double layer vegetation effects,the flow structure and turbulence characteristics are often complicated and changes dramatically,especially at top of the tall and short vegetation layer.