摘要
为了研究管内低浓度液固两相流颗粒运动特性,提出一种基于PIV图像处理法的液固两相流颗粒速度场、涡量场及速度大小的分析方法。通过高速摄影仪获得不同工况下流场的运动图像,运用Canny算子边缘检测法分割图像提取粒子,由互相关函数获得粒子速度和方向,重建二维场。速度矢量场与颗粒运动轨迹相符,说明该方法可用于管内低浓度液固两相流动测量。研究发现:流量越大,流场越复杂,颗粒速度分布越混乱,涡量变化范围越大。流量、浓度和粒径对颗粒速度有显著影响。颗粒速度随浓度、粒径的增大而减小,而随流量增大正好相反。水平管中,颗粒粒径越小,颗粒速度增幅越大,最大约为2倍;流量越大,不同粒径组合下颗粒速度差越大,约达1.5倍。
To study the flow characteristics of particles in solid-liquid pipe flow at low solid volume fractions, this paper proposed a method for analyzing the particle velocity field, vorticity field and velocity using Particle-image Velocimetry（PIV） image processing. With a high speed camera, image sequences of the flow field in different working conditions were obtained. The flow field of particles was obtained using cross-correlation to reconstruct the two-dimensional field after image segmentation using canny algorithm and particle extraction. The fact showed that the velocity field was consistent with the particle trajectories, showing that this method could be used for solid-liquid two-phase flow at low solid volume fractions. The results showed that greater flow rate resulted in more complex flow field with more chaotic velocity distributions and larger vorticity variations. The flow rate,concentration and particle size had a significant impact on the particle velocity. The particle velocity decreased with the concentration and particle size, but increased with flow rate. In horizontal pipe,the smaller the particle size was, the greater the growth rate was, and whose maximum could be double the minimum value. Furthermore the greater the flow rate was, the bigger the particle speed difference under different particle sizes, whose maximum could be 1.5 times the minimum value.
作者
王丽燕
孙志强
周天
檀妹静
WANG Li-Yan1,2 SUN Zhi-Qiang2 Zhou Tian2 TAN Mei-Jing1(1. Science and Technology on Space Physics Laboratory, China Academy of Launch Vehicle Technology, Beijing 100076, China; 2. School of Energy Science and Engineering, Central South University, Changsha 410083, Chin)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2018年第9期1970-1978,共9页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.51576213)
湖南省科技计划项目(No.2015RS4015)
关键词
液固两相流
PIV法
速度场
涡量场
颗粒速度
solid-liquid two-phase flow
PIV
velocity field
vorticity field
velocity of particles
