堆积体作用下水流三维结构分析.doc

受堆积体影响的河道三维水流结构研究 黄小利1，郭志学1*，李 彬，李 果1，张 婧 （1.四川大学 水力学与山区河流开发保护国家重点实验室，四川 成都 610065; 610041;3.西华大学 能源与动力工程学院，四川 成都 610039） 摘 要：通过水槽试验研究了在堆积体影响下的三维水流结构，采用ADV测量了堆积影响河段的三维流速：断面纵向最大流速从堆积体段逐渐偏向右岸，且逐渐向河床底部移动，往下游又逐渐上升并恢复至天然状态。主流受收缩加速影响，越过堆积体后，呈水跃流态。受堆积体挤压流路和水流惯性的影响，主流流速在靠近堆积体略下游位置出现最大值。横向流速在堆积体段出现了正负值交替，某一水深处的流速为零，在该水深的上层，水流偏向堆积体岸流动，在该水深的下层，水流偏向右岸流动，上下层水流出现了反向流动，同时垂向流速在堆积体段也出现了正负值交替，表明在试验段水流呈类螺旋流流态。受堆积体作用，水流从表层到床面不等宽收缩，在堆积体段水流呈逆时针螺旋流与纵向水跃交互作用，水流呈复杂的三维状态。 关键词：堆积体三维速分布螺旋流;水跃 中图分类号：TV143.1 文献标志码：A Study on Three-dimensional Flow Structure of River Channel Under the Effect of Congeries HUANG Xiaoli1,GUO Zhixue1*,LI Bin2,LI Guo1,ZHANG Jing3 (1.State Key Lab. of Hydraulic and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China； 2.Wuhan Municipal Engineering Design Research Institute Co., Ltd. Chengdu branch, Chengdu 610041,China; 3.School of Energy and Power Engineering,Xihua University,Chengdu 610039, China) Abstract:Flow structure will become more complex when there are large scale congeries in the river.However,three-dimensional flow structure characteristics are paid little attention.Based on the flume experiment study,the three-dimensional flow structure of river channel under the influence of congeries has been studied,and the velocity has been measured using the Acoustic Doppler Velocimeter(ADV).Through the analyses of the velocity around the congeries at different plane,results show that it leads to water block at theupstream of congeries,and then appears waterfall.The direction of the maximum longitudinal velocity from the congeries gradually turns to the right bank and the bottom of the riverbed in the vertical,and then rise and return to the natural state at the downstream of congeries.The main stream is in hydraulic jump state affected by the shrinkage of the river section around the congeries.Under the influence of the flow area of the river section cutted down and the inertia of the flow,the maximum velocity occurs in the downstream pos