Dynamic water fill level measurement using a phantom-dependent adaptive electrical capacitance tomography (ECT) method

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christoph Kandlbinder-Paret ◽  
Alice Fischerauer ◽  
Gerhard Fischerauer
Keyword(s):  
Pipe Wall ◽  
Electrical Capacitance Tomography ◽  
Electrical Capacitance ◽  
Capacitance Measurements ◽  
Level Measurement ◽  
Element Simulation ◽  
Fill Level ◽  
Capacitance Tomography ◽  
Low Permittivity ◽  
Adaptation Scheme

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.

scholarly journals Modeling and Calibration of Electrical Capacitance Tomography Sensor for Medical Imaging

2018 ◽  
Vol 11 (3) ◽  
pp. 1471-1477 ◽  
Author(s):  
M. Ambika ◽  
S. Selva Kumar
Keyword(s):  
Imaging Techniques ◽  
Low Cost ◽  
Dielectric Medium ◽  
Capacitance Measurement ◽  
Electrical Capacitance Tomography ◽  
Electrical Capacitance ◽  
Cross Sectional ◽  
Capacitance Measurements ◽  
Electrode Capacitance ◽  
Capacitance Tomography

Electrical Capacitance Tomography (ECT) is an imaging technique which generates a cross-sectional image representing the internal permittivity distribution based on external capacitance measurements. It possesses the advantages of being non-radioactive, non-intrusive, non-invasive, high imaging speed and low cost over the conventional imaging techniques. Inter-electrode capacitance measurements are done by exciting electrodes placed around the non-conductive dielectric medium cylinder inside which, the material to be imaged is placed. This paper emphasizes on modelling and calibrating an electrical capacitance tomography sensor using ANSYS APDL with medium as air, water and extending the procedure for normal bone and cracked bone. ECT sensor is modelled by mounting 12 electrodes symmetrically outside the cylinder. The cylinder is made up of Polyvinyl Chloride (PVC) which is non-conductive dielectric medium while the electrodes are made up of Copper (Cu) which is conductive. The electrodes are excited in pairs and the potential distribution which is based on permittivity of the medium is analysed using ANSYS and the capacitance between the electrodes were calculated. The entire electrode modelling, calibration and capacitance measurement for the simulated bone model with and without crack is presented in this paper.

A Review on Electrical Capacitance Tomography Sensor Development

2015 ◽  
Vol 73 (3) ◽  
Author(s):  
Noor Amizan Abd. Rahman ◽  
Ruzairi Abdul Rahim ◽  
Abdullah Mohd Nawi ◽  
Leow Pei Ling ◽  
Jaysuman Pusppanathan ◽  
...  
Keyword(s):  
Pipe Wall ◽  
Electrical Capacitance Tomography ◽  
Electrical Capacitance ◽  
Design Factor ◽  
Factor Design ◽  
Matters Of Concern ◽  
The Cost ◽  
Sensor System Design ◽  
Capacitance Tomography ◽  
Design Factors

Electrical Capacitance Tomography (ECT) detects changes in the distribution of transparency in enclosed areas or pipes. Until now, various methods have been used to determine the optimum ECT sensor for a particular application. Some important parameters that affect the sensitivity of the sensor cannot be ignored. Design factors discussed in this paper study the needs in industry by producing the best image, without affecting the operation of the process. From previous studies many parameters influence the quality and effectiveness of an ECT sensor. The parameters that play important roles in ECT sensor design include the thickness and type of material in the pipe wall between the electrodes and the sensing zone, the thickness and material of the pipe wall separating the electrodes and the screen, the size of the electrodes, the guarding used, example radial guards or plane axial guards, and whether end guards are used. Other matters of concern regarding the dimension and the distance between the electrodes with guardians it is important design factor. Electrodes positioned either inside or outside the vessel will affect the cost factor design to the type of system to be used. This overview of the study is a basic guide for the essential requirements for an ECT sensor system design.

DESIGN OF FLEXIBLE ELECTRICAL CAPACITANCE TOMOGRAPHY SENSOR

2015 ◽  
Vol 77 (28) ◽  
Author(s):  
MT Masturah ◽  
MHF Rahiman ◽  
Zulkarnay Zakaria ◽  
AR Rahim ◽  
NM Ayob
Keyword(s):  
Outer Layer ◽  
Electrical Capacitance Tomography ◽  
Electrical Capacitance ◽  
Capacitance Tomography ◽  
Fluid Imaging

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.

Image Fusion of ECT/ERT for Oil-Gas-Water Three-Phase Flow

2011 ◽  
Vol 3 (2) ◽  
pp. 29-34 ◽  
Author(s):  
Lifeng Zhang
Keyword(s):  
Image Fusion ◽  
Electrical Capacitance Tomography ◽  
Phase Flow ◽  
Electrical Capacitance ◽  
Cross Sectional ◽  
Three Phase ◽  
Three Phase Flow ◽  
Capacitance Tomography ◽  
Oil Gas ◽  
Image Fusion Method

The tomographic imaging of process parameters for oil-gas-water three-phase flow can be obtained through different sensing modalities, such as electrical resistance tomography (ERT) and electrical capacitance tomography (ECT), both of which are sensitive to specific properties of the objects to be imaged. However, it is hard to discriminate oil, gas and water phases merely from reconstructed images of ERT or ECT. In this paper, the feasibility of image fusion based on ERT and ECT reconstructed images was investigated for oil-gas-water three-phase flow. Two cases were discussed and pixel-based image fusion method was presented. Simulation results showed that the cross-sectional reconstruction images of oil-gas-water three-phase flow can be obtained using the presented methods.

scholarly journals 3D-Printed Multilayer Sensor Structure for Electrical Capacitance Tomography

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3416 ◽  
Author(s):  
Aleksandra Kowalska ◽  
Robert Banasiak ◽  
Andrzej Romanowski ◽  
Dominik Sankowski
Keyword(s):  
Industrial Applications ◽  
Industrial Test ◽  
Electrical Capacitance Tomography ◽  
Geometrical Parameters ◽  
Electrical Capacitance ◽  
Low Contrast ◽  
Sensor Structure ◽  
Internal Measurement ◽  
3D Printed ◽  
Capacitance Tomography

Presently, Electrical Capacitance Tomography (ECT) is positioned as a relatively mature and inexpensive tool for the diagnosis of non-conductive industrial processes. For most industrial applications, a hand-made approach for an ECT sensor and its 3D extended structure fabrication is used. Moreover, a hand-made procedure is often inaccurate, complicated, and time-consuming. Another drawback is that a hand-made ECT sensor’s geometrical parameters, mounting base profile thickness, and electrode array shape usually depends on the structure of industrial test objects, tanks, and containers available on the market. Most of the traditionally fabricated capacitance tomography sensors offer external measurements only with electrodes localized outside of the test object. Although internal measurement is possible, it is often difficult to implement. This leads to limited in-depth scanning abilities and poor sensitivity distribution of traditionally fabricated ECT sensors. In this work we propose, demonstrate, and validate experimentally a new 3D ECT sensor fabrication process. The proposed solution uses a computational workflow that incorporates both 3D computer modeling and 3D-printing techniques. Such a 3D-printed structure can be of any shape, and the electrode layout can be easily fitted to a broad range of industrial applications. A developed solution offers an internal measurement due to negligible thickness of sensor mount base profile. This paper analyses and compares measurement capabilities of a traditionally fabricated 3D ECT sensor with novel 3D-printed design. The authors compared two types of the 3D ECT sensors using experimental capacitance measurements for a set of low-contrast and high-contrast permittivity distribution phantoms. The comparison demonstrates advantages and benefits of using the new 3D-printed spatial capacitance sensor regarding the significant fabrication time reduction as well as the improvement of overall measurement accuracy and stability.

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