摘要
有压管道系统中因钝体存在而形成的圆形断面到环状断面突缩在管道内会产生显著的能量损失,流动现象是能耗的直接体现。本研究采用物理模型试验和数值模拟相结合的方法获取了收缩面下游为环状缝隙的突缩流场的可视化结果。结果表明:收缩比直接影响流动现象的变化,收缩面上游无静止涡,流动分离将环状缝隙内流场分为回流区、剪切层和主流区,缝隙收缩点和再附着点出现在环状缝隙流场中。基于数值模拟和试验结果得到本研究模型收缩系数的表达式,缝隙收缩点和再附着点的轴向位置与收缩比强相关,并用指数函数进行表示。
In pressurized pipeline systems,the transition from a circular to an annular cross-section due to the presence of a blunt body causes significant energy losses within the pipeline,with flow phenomena directly influencing energy consumption.This study integrates physical experiments and numerical simulations to visualize the flow field of sudden contraction with an annular gap downstream of the contraction surface.The findings demonstrate that the contraction ratio distinctly influences changes in flow phenomena.Upstream of the contraction surface,no stagnant vortex exists;instead,flow separation divides the flow field inside the annular gap into recirculation zones,shear layers,and mainstream regions.The Vena-contracta Point and Reattachment Point manifest in the flow field of the annular gap.Through CFD and experimental results,this study derives an expression for the contraction coefficient in its model,where the axial positions of the Vena-contracta Point and Reattachment Point exhibit a strong exponential correlation with the contraction ratio.
作者
宋晓腾
李永业
孙西欢
马娟娟
李飞
SONG Xiaoteng;LI Yongye;SUN Xihuan;MA Juanjuan;LI Fei(Taiyuan University of Technology,Taiyuan 030024,China)
出处
《中国水利水电科学研究院学报(中英文)》
北大核心
2025年第1期46-53,共8页
Journal of China Institute of Water Resources and Hydropower Research
基金
国家自然科学基金项目(51179116)
山西省自然科学基金项目(202303021211141)。
关键词
突缩流场
流动结构
收缩系数
缝隙收缩点
再附着点
sudden contraction flow field
flow structure
contraction coefficient
vena-contracta point
reattachment point
作者简介
宋晓腾(1997-),博士生,主要从事水力学、流体力学及流体机械研究。E-mail:songxiaoteng0106@link.tyut.edu.cn;通信作者:孙西欢(1960-),博士,教授,主要从事水力学、流体力学及流体机械研究。E-mail:sunxihuan@tyut.edu.cn。
