Traditional methods for measuring the residence time distribution (RTD) of particles in a fluidized bed are complex and time-consuming. To this regard, the present work proposes a new measurement method with remarkable efficiency based on digital image analysis. The dyed tracers are recognized in the images of the samples due to the difference of colors from bed materials. The HSV and the well-known RGB color space were employed to distinguish the tracers. By enhancing the Saturation and the Value in HSV and adjusting the gray range of images, the recognition error is effectively reduced. Then the pixels representing the tracers are distinguished, based on which the concentration of the tracers and RTD are measured. The efficiency, accuracy and repeatability of the method were validated by RTD measurements experiments. The method is also fit for distinguishing the target particles from multi-component systems consisting of particles of different colors.

中文翻译：

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基于数字图像分析的流化床颗粒停留时间分布测量方法

用于测量颗粒在流化床中的停留时间分布（RTD）的传统方法既复杂又费时。为此，本工作提出了一种基于数字图像分析的，效率显着的新测量方法。由于床料的颜色不同，染色的示踪剂在样品图像中被识别。HSV和众所周知的RGB颜色空间用于区分示踪剂。通过增强HSV中的饱和度和值并调整图像的灰度范围，可以有效减少识别错误。然后区分代表示踪剂的像素，据此测量示踪剂和RTD的浓度。RTD测量实验验证了该方法的有效性，准确性和可重复性。