基于轨迹图像灰度分布的颗粒速度测量  

Particle velocity measurement based on gray value distribution of trajectory image

作　　者：周骛[1] 邵星翔 陈本珽 蔡小舒[1] ZHOU Wu;SHAO Xingxiang;CHEN Benting;CAI Xiaoshu(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学能源与动力工程学院

出　　处：《能源研究与信息》2019年第3期156-162,179,共8页Energy Research and Information

基　　金：国家自然科学基金资助项目(51576130)

摘　　要：在对单帧长曝光成像法形成的颗粒轨迹灰度值进行理论分析的基础上,提出了基于灰度值分布的颗粒速度测量方法,即对轨迹长轴一端的像素相对灰度值ΔG沿轴向x进行线性拟合,可获得拟合斜率-Pk/v,其中常数k由标定实验预先获得,从而可计算出颗粒速度。基于成像仿真分析和实验研究,对该方法的速度测量误差进行了分析,并与前期工作中采用的直接二值化方法结合Regionprops函数或Radon变换测速的误差进行对比,结果表明,在该实验条件下,基于图像灰度分布的方法可将测速误差减小5%~25%。Based on the theoretical analysis of the gray value of the particle trajectory formed by the single-frame long-exposure imaging method,a particle velocity measurement method was proposed based on the gray value distribution.A linear fitting was performed on the relative gray value ΔG along long axis x of the trajectory and then the linear fitting coefficient -Pk/v could be obtained.The system constant k could be calibrated in advance and particle velocity could then be calculated.Based on the imaging simulation analysis and experimental studies,the measurement error of this method was analyzed and compared with the direct binarization method combined with the Regionprops function adopted in the previous works or Radon transform.The results showed that the method based on the image gray distribution could reduce the error by 5%~25%under the experimental conditions in this paper.

关 键 词：轨迹图像法 图像灰度值 线性拟合 误差 

分 类 号：TP392[自动化与计算机技术—计算机应用技术]