化工进展Chemical Industry and Engineering Progress2024 年第 43 卷第 2 期离焦图像法颗粒多参数在线测量技术周骛1，2，龚文超1，2，徐日辛1，2（1 上海理工大学能源与动力工程学院，上海 200093；2上海市动力工程多相流动与传热重点实验室，上海 200093）摘要：图像法颗粒在线分析技术可以获得稀疏颗粒两相流中颗粒相的速度、粒度以及数目浓度等参数及其三维分布，具有非侵入、系统操作简便、结果直观等优点，但由于成像系统景深有限，易导致成像的离焦模糊，阻碍了其在颗粒在线测量方面的应用。
然而颗粒图像的离焦模糊程度其实蕴含了颗粒的深度位置等信息，利用离焦模糊进行颗粒关键参数测量的技术逐渐得到研究人员重视。
本文回顾了离焦图像法颗粒多参数测量的发展历史，简述了三种典型的离焦法（基于单相机的特殊光阑法和像散法，以及基于双相机的异像距法）颗粒深度位置测量原理，分析了不同方法的优劣势，指出在深度学习等先进图像处理算法的加持下，离焦图像法有望在颗粒在线测量领域得到更加广泛应用。
关键词：图像法；离焦；速度；粒度；颗粒测量中图分类号：TH89 文献标志码：A 文章编号：1000-6613（2024）02-0586-07Online measurement techniques for multi-parameters of particlesbased on defocus imagingZHOU Wu 1，2，GONG Wenchao 1，2，XU Rixin 1，2(1 School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;2Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, Shanghai 200093, China)Abstract: The imaging technique for particle online analysis can obtain parameters, including velocity, particle size, number, and concentration of the particle phase in sparse two-phase flow, and their three-dimensional distribution. This technique is non-invasive, simple to operate, and provides intuitive results. However, the limited depth of field in the imaging system can lead to defocus blur, which hinders its application in online particle measurement. In fact, the degree of defocus blur of the particle image contains the depth position information of particles, and the use of defocus blur to measure key particle parameters has attracted increasing attention from researchers. This paper reviews the development history of multi-parameter measurement of particles by defocusing image method. The principle of depth measurement of 3 typical defocus methods (special diaphragm method and astigmatism method based on a single camera, and two-imaging distance method based on two cameras) is briefly described. The advantages and disadvantages of different methods are analyzed. It is pointed out that with the support of advanced image processing algorithms, such as deep learning, defocus imaging method will be more widely used in the field of online particle measurement.综述与专论DOI ：10.16085/j.issn.1000-6613.2023-1941收稿日期：2023-11-06；修改稿日期：2023-12-29。
