International Society for Industrial Process Tomography

Study on Image Reconstruction of Capacitively Coupled Electrical Resistance Tomography using Total Impedance: Sensitivity Distributions

Yuxin Wang, Junchao Huang, Baoliang Wang^*, Zhiyao Huang^*, Haifeng Ji and Haiqing Li

State Key Laboratory of Industrial Control Technique, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, People’s Republic of China

^*Email: wangbl@zju.edu.cn, zy_huang@zju.edu.cn

ABSTRACT

This work aims to investigate the image reconstruction of capacitively coupled electrical resistance tomography (CCERT) by using total impedance (including the real part, the imaginary part and the amplitude) of gas-liquid two-phase flow. As a preliminary study, this work is the first step and focuses on investigating the total impedance sensitivity distributions of CCERT. A mathematical model is established and three groups of sensitivity distributions (for the real part, the imaginary and the amplitude of the impedance of gas-liquid two-phase flow, respectively) are obtained. With the practical impedance data obtained by a 12-electrode CCERT prototype, the practical image reconstruction experiments are carried out to reconstruct the phase distribution images of the gas-liquid two-phase flow by linear back projection (LBP) algorithm. The research results show that there is no negative region exists in the three groups of sensitivity distributions (for the real part, the imaginary part and amplitude, respectively) and all the three groups of sensitivity distributions are not uniform. The sensitivity distribution for the real part of the total impedance has the highest average sensitivity and the largest average uniformity coefficient. All the three parts of the impedance contain useful information of the gas-liquid two-phase flow. The reconstructed images of CCERT by using the three parts of the impedance information can reflect the phase distribution of the gas-liquid two-phase flow in the pipe.

Keywords processing tomography, electrical resistance tomography, impedance, sensitivity distribution, image reconstruction

Industrial Application gas and liquid