基于非接触式静电传感阵列的二维流化床气泡参数测量

Non-contact electrostatic sensing array for 2-demisional measurement and characterization of bubble in fluidized bed

中文关键词: 流化床  静电传感器阵列  互相关法  气泡速度  气泡直径

英文关键词: fluedized bed  electrostatic sensor array  cross-correlation technique  bubble velocity  bubble size

中文摘要:

      实现流化床内气泡参数实时在线测量与表征，对深入了解流化床内气固流动特性以及反应过程调控具有重要意义。本文提出一种非接触静电传感阵列的气泡参数测量方法，通过静电传感器结合互相关法测量气泡上升速度，进一步利用气泡流经传感器的时间差，可获得气泡直径。开发了非接触式多路检测系统，并在二维流化床上开展了气泡特性实验研究。结果表明：静电传感器阵列结合互相关技术可实现在流化床内气泡上升速度、直径的同时测量；不同工况下，二维流化床中气泡的流动特性基本满足Davidson半经验公式，气泡的上升速度与流化风速及气泡直径的平方根成线性关系。非接触静电传感阵列对气泡流动不产生干扰，在表征流化床内部气泡流动特性具有重要的工程应用价值。

英文摘要:

      Online measurement and characterization of bubble parameters in the fluidized bed is of great significance for in-depth understanding of the gas-solid flow characteristics in the fluidized bed and the regulation of the reaction process. A method for measuring bubble parameters with non-contact electrostatic sensing array is proposed. The rising speed of bubble is measured by the electrostatic sensor combined with the cross-correlation algorithm. The bubble diameter is calculated with the time difference of the bubble flowing through the sensor. A non-contact multiplex detection system is developed, and an experimental study of bubble characteristics is carried out on a two-dimensional fluidized bed. The results show that the electrostatic sensor array combined with the cross-correlation algorithm can realize the simultaneous measurement of the rising velocity and diameter of the bubbles in the fluidized bed. Under different conditions, the flow characteristics of the bubbles in the two-dimensional fluidized bed basically satisfy the Davidson semi-empirical formula. The rising velocity of bubble has a linear relationship with the fluidizing wind velocity and the square root of the bubble diameter. The non-contact electrostatic sensing array does not interfere with the bubble flow, so it has great and potential applications in characterization of the bubble flow characteristics in the fluidized bed.