Three-dimensional electrical capacitance tomography in rectangular spouted bed

doi:10.11949/j.issn.0438-1157.20180086

Abstract

Abstract:

A 32-electrode electrical capacitance volume tomography (ECVT) system was designed to investigate the characteristics of particles flow in rectangular spouted bed. To calculate the sensitive field, the finite element simulation model was established. The sensor characteristics were simulated and analyzed. The accuracy of sensitive field was verified by imaging. By making scale solid model, the capacitance of electrode couples attached around the model was carried out by using the system. Linear back projection (LBP) algorithm was adopted to reconstruct the distribution of three-dimensional dielectric constant in the bed. The results indicated that the 32-electrode ECVT system can detect the regular movement of particles from static to circular in the spouted bed effectively, which provided another effective method for the research of motion characteristics of particles in the spouted bed.

Key words: ECVT, spouted bed, tomography, two-phase flow, sensitivity map, LBP algorithm, measurement

摘要：

设计了32电极三维电容层析成像（ECVT）系统用于矩形喷动床内颗粒流动特性的研究。建立有限元仿真模型并计算灵敏场，对传感器特性进行仿真分析并成像验证了该灵敏场的准确性。搭建同尺寸的喷动床，应用32电极ECVT数据采集系统获取喷动床ECVT电极对间电容，选用线性反投影（LBP）算法重建床内三维介电常数分布。实验结果显示，研发的32电极ECVT系统可以有效地检测到喷动床内部颗粒从静止到循环运动全过程的规律性运动，从而为喷动床内部颗粒运动特性的研究提供了有效手段。

关键词: ECVT, 喷动床, 成像, 两相流, 灵敏场, LBP算法, 测量

CLC Number:

TB934

SUN Yang, YANG Daoye, LIU Dazhen, FENG Wenxuan, GU Muyang. Three-dimensional electrical capacitance tomography in rectangular spouted bed[J]. CIESC Journal, 2018, 69(8): 3383-3389.

孙阳, 杨道业, 刘大震, 封文轩, 顾沐阳. 矩形喷动床三维电容层析成像[J]. 化工学报, 2018, 69(8): 3383-3389.

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