Multi-phase permittivity reconstruction in electrical capacitance tomography by level-set methods

2007 ◽  
Vol 15 (3) ◽  
pp. 213-247 ◽  
Author(s):  
Weifu Fang
Sensor Review ◽  
2016 ◽  
Vol 36 (4) ◽  
pp. 429-445 ◽  
Author(s):  
Ziqiang Cui ◽  
Qi Wang ◽  
Qian Xue ◽  
Wenru Fan ◽  
Lingling Zhang ◽  
...  

Purpose Electrical capacitance tomography (ECT) and electrical resistance tomography (ERT) are promising techniques for multiphase flow measurement due to their high speed, low cost, non-invasive and visualization features. There are two major difficulties in image reconstruction for ECT and ERT: the “soft-field”effect, and the ill-posedness of the inverse problem, which includes two problems: under-determined problem and the solution is not stable, i.e. is very sensitive to measurement errors and noise. This paper aims to summarize and evaluate various reconstruction algorithms which have been studied and developed in the word for many years and to provide reference for further research and application. Design/methodology/approach In the past 10 years, various image reconstruction algorithms have been developed to deal with these problems, including in the field of industrial multi-phase flow measurement and biological medical diagnosis. Findings This paper reviews existing image reconstruction algorithms and the new algorithms proposed by the authors for electrical capacitance tomography and electrical resistance tomography in multi-phase flow measurement and biological medical diagnosis. Originality/value The authors systematically summarize and evaluate various reconstruction algorithms which have been studied and developed in the word for many years and to provide valuable reference for practical applications.


Author(s):  
E. Al Hosani ◽  
M. Soleimani

Multiphase flow imaging is a very challenging and critical topic in industrial process tomography. In this article, simulation and experimental results of reconstructing the permittivity profile of multiphase material from data collected in electrical capacitance tomography (ECT) are presented. A multiphase narrowband level set algorithm is developed to reconstruct the interfaces between three- or four-phase permittivity values. The level set algorithm is capable of imaging multiphase permittivity by using one set of ECT measurement data, so-called absolute value ECT reconstruction, and this is tested with high-contrast and low-contrast multiphase data. Simulation and experimental results showed the superiority of this algorithm over classical pixel-based image reconstruction methods. The multiphase level set algorithm and absolute ECT reconstruction are presented for the first time, to the best of our knowledge, in this paper and critically evaluated. This article is part of the themed issue ‘Supersensing through industrial process tomography’.


2013 ◽  
Vol 734-737 ◽  
pp. 3016-3021 ◽  
Author(s):  
Hai Yan Cao ◽  
Xue Mei Duan ◽  
Hua Xiang Wang

Electrical Capacitance Tomography technique is a new technique for multi-phase flow measurement. With broad application prospects, the purpose of this technique is to identify each phases composition of two-phase/multi-phase flow system in a closed pipe. A new method COMSOL was used to analysis the electrical capacitance tomography of reconstruction image and simulation research. First of all, different electrical models were established, and the reconstruction images of four kinds of representative flow were achieved; In addition, through simulation study of the field with disperse phase, the influence of the electrode number, shielding case and radial electrode to the imaging quality were analyzed; Finally, the reconstruction images of three-phase flow were achieved to obtain the satisfactory result.


2015 ◽  
Vol 77 (28) ◽  
Author(s):  
MT Masturah ◽  
MHF Rahiman ◽  
Zulkarnay Zakaria ◽  
AR Rahim ◽  
NM Ayob

This paper discussed the design–functionality and application of Flexible Electrical Capacitance Tomography sensor (FlexiECT). The sensors consist of 12 electrodes allocated surrounding the outer layer of the pipeline. The sensor is designed in such that the flexibility features suit the applications in the pipeline of multiple size. This paper also discussed the preliminary result of FlexiECT applications in fluid imaging by identifying the percentage of two mixing fluids.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christoph Kandlbinder-Paret ◽  
Alice Fischerauer ◽  
Gerhard Fischerauer

Abstract In electrical capacitance tomography (ECT), the resolution of the reconstructed permittivity distribution improves with the number of electrodes used whereas the number of capacitance measurements and the measurement time increases with the number of electrodes. To cope with this tradeoff, we present a phantom-dependent adaptation scheme in which coarse measurements are performed with terminal electrodes interconnected to form a synthetic electrode ring with fewer but larger electrodes. The concept was tested by observing the sloshing of water inside a pipe. We compare the reconstructed results based on eight synthetic electrodes, on 16 elementary electrodes, and on the adaptation scheme involving both the eight synthetic electrodes and some of the elementary capacitances. The reconstruction used the projected Landweber algorithm for capacitances determined by a finite-element simulation and for measured capacitances. The results contain artefacts attributed to the influence of the high permittivity of water compared to the low permittivity of the pipe wall. The adaptation scheme leads to nearly the same information as a full measurement of all 120 elementary capacitances but only requires the measurement of 30 % fewer capacitances. By detecting the fill level using a tomometric method, it can be determined within an uncertainty of 5 % FS.


Sign in / Sign up

Export Citation Format

Share Document