淹没阶梯形丁坝水流结构PIV试验研究  

PIV experimental study on flow structure of submerged step-shaped spur dike

作　　者：王世鹏 钟亮[1,2] 廖尚超[1] 邓晓龙 WANG Shi-peng;ZHONG Liang;LIAO Shang-chao;DENG Xiao-long(School of River&Ocean Engineering,Chongqing Jiaotong University,Chongqing 400074,China;National Engineering Research Center for Inland Waterway Regulation,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学河海学院,重庆400074 [2]重庆交通大学,国家内河航道整治工程技术研究中心,重庆400074

出　　处：《水运工程》2022年第1期100-111,共12页Port & Waterway Engineering

基　　金：重庆市基础科学与前沿技术研究项目(cstc2017jcyjAX0278);重庆交通大学大学生创新创业训练计划资助项目(202010618002)。

摘　　要：阶梯形丁坝在航道整治中应用广泛,但其水流结构研究仍不充分。基于PIV室内水槽试验,探讨阶梯形丁坝区无量纲纵向时均流速u^(+)、紊动强度T^(+)_(u)、雷诺应力R^(+)和紊动能E^(+)的分布规律。结果表明:丁坝水流在纵剖面上可划分为顺流区、回流区和过渡区,丁坝内侧至一级丁坝坝头各剖面u^(+)高速区位于坝顶上部,低速区和回流区位于坝顶下部;丁坝外侧各剖面u^(+)沿程变化表现为先增大后减小。受水流翻越坝顶影响,丁坝上游各垂线的T^(+)_(u)随y^(+)变化明显,而下游各垂线的T^(+)_(u)变化相对平缓。R^(+)高值区位于坝顶附近且呈带状,流量较小时,R^(+)沿y^(+)的垂线变化相对平缓,坝顶附近R^(+)分布曲线呈“S”形,流量增大后丁坝上游R^(+)变化加剧。E^(+)高值区由坝顶向水槽底部和水面扩散呈三角状,且E^(+)随流量的增加而增大。Step-shaped spur dike is widely used in waterway regulation,but its flow structure is still not fully studied.Based on the PIV indoor flume test,we discuss the distribution of dimensionless longitudinal time average velocity u^(+),turbulence intensity T^(+)_(u),Reynolds stress R^(+) and turbulent kinetic energy E^(+) in the stepped spur dike area.The results show that the longitudinal section of spur dike flow can be divided into downstream area,reflux area and transition area.The high velocity area of u^(+) for each profile from the inside of spur dike to the head of the first step spur dike is located in the upper part of the dam crest,while the low velocity area and the reflux area are located in the lower part of the dam crest,the u^(+) of section outside spur dike variation first increases and then decreases.Affected by the flow over the dam crest,T^(+)_(u) of vertical line upstream of spur dike change obviously with y^(+),while T^(+)_(u) of vertical line downstream of spur dike change relatively gentle with y^(+).The high value area of R^(+) is located near the dam crest and is in a strip shape.When the discharge is small,the vertical change of R^(+) with y^(+) is relatively gentle,and the distribution curve of R^(+) near the dam crest is in“S”shape.The change of R^(+) in the upstream of spur dike is intensified with the increase of discharge.The high value area of E^(+) diffuses from the top of the dam to the bottom of the flume and water surface in a triangular shape,and E^(+) increases with the increase of discharge.

关 键 词：阶梯形丁坝 明槽紊流 时均流速 紊动强度 雷诺应力 紊动能 

分 类 号：TV863[水利工程—水利水电工程] U617.9[交通运输工程—船舶及航道工程]