摘要
以90°圆形截面弯管为研究对象，以水为介质对管内流场采用4种模型进行数值模拟，并与实验值对比．结果表明，在Re=-13000-60000条件下，大涡模拟模型在弯管区的时均速度和压力降与实验值吻合较好，Re=-60000时下弯管区不同角度横截面处流场二次流有2个主涡，位置由对称半截面附近逐渐向弯管内侧发展，同时形成一个由弯管壁面和管中二次流综合诱导引起的马蹄涡；弯管段静压力分布显示，45°横截面弯管内、外两侧的压力差最大，此角度是流体出现流动分离现象的临界角度．
The flow field in a circular-sectioned 90° bending tube is numerically simulated by using four models with water as medium, and compared with the experimental values. The results show that the time average velocity and pressure drop of the large eddy simulation （LES） model in the curved section are consistent with experimental values when the Reynolds number （Re） ranges from 13 000-60 000. Using the LES model, the flow field characteristics on the cross section with different angles are analyzed in the curved section when Re=60000, two primary eddies in the secondary flow on the cross section are found, their positions change from the symmetric half section to the inside of bending tube, while horseshoe vortex is induced comprehensively by the bending tube wall and secondary flow in the tube. The distribution characteristics of static pressure in the curved section show that the pressure difference value of both bending tube inside and outside reaches the maximum on the 45° cross section. This angle is the critical angle when fluid flow separation occurs.
出处
《过程工程学报》
CAS
CSCD
北大核心
2013年第5期760-765,共6页
The Chinese Journal of Process Engineering
基金
教育部科学技术研究重点资助项目(编号:212030)
辽宁省高等学校优秀人才支持计划资助项目(编号:LJQ2011036)
关键词
90°弯管
大涡模拟
流线
压力
90° bending tube
large eddy simulation
flow field
pressure
