Electrical Capacitance Tomography—Sensor Models, Design, Simulations, and Experimental Verification

Alme, K.J.; Mylvaganam, Saba

doi:10.1109/jsen.2006.881409

Cited by 106 publications

(43 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This implies the necessity to search for the most favorable geometric layout and the number of electrodes (Wang F. et al 2010a), often using optimisation methods. The need for simulation studies leading to optimise sensors was already noticed (Yan et al 1999), but currently it is the basis for design of modern ECT systems (Alme and Mylvaganam, 2006). Makkawi and Wright (2002b) indicated the important impact of dynamic properties (eg.…”

Section: Current Applications Of Ect Tomography For Research On Fluidmentioning

confidence: 99%

Applications of Electrical Capacitance Tomography for Research on Phenomena Occurring in the Fluidised Bed Reactors

Porzuczek¹

2014

Chemical and Process Engineering

View full text Add to dashboard Cite

The paper presents a review of current achievements in the Electrical Capacitance Tomography (ECT) in relation to its possible applications in the study of phenomena occurring in fluidised bed reactors. Reactors of that kind are being increasingly used in chemical engineering, energetics (fluidised bed boilers) or industrial dryers. However, not all phenomena in the fluidised bed have been thoroughly understood. This results in the need to explore and develop new research methods. Various aspects of ECT operation and data processing are described with their applicability in scientific research. The idea for investigation of temperature distribution in the fluidised bed, using multimodal tomography, is also introduced. Metrological requirements of process tomography such as sensitivity, resolution, and speed of data acquiring are noted.

show abstract

Section: Current Applications Of Ect Tomography For Research On Fluidmentioning

confidence: 99%

Applications of Electrical Capacitance Tomography for Research on Phenomena Occurring in the Fluidised Bed Reactors

Porzuczek¹

2014

Chemical and Process Engineering

View full text Add to dashboard Cite

show abstract

“…Other applications of interdigital dielectrometry sensors proposed include detection of landmines [31], the detection of dangerous materials for security applications [32], and the monitoring of curing pro- cesses [33]. Electric Capacitance Tomography (ECT) is a similar measurement system for detection of dielectrics [34].…”

Section: Measurement Techniques From Previous Researchmentioning

confidence: 99%

“…The hardware should support the short circuit current mode and provide a means of increasing the feedback capacitance to avoid saturation. Using the inversion techniques frequently used for electrical capacitance tomography (ECT) should also be explored [34]. With these additional capabilities a new frontier of possibilities exists to perform experiments beyond consideration using the existing hardware.…”

Section: Multichannel Sensingmentioning

confidence: 99%

Dielectrometry Measurements of Moisture Diffusion and Temperature Dynamics in Oil Impregnated Paper Insulated Electric Power Cables

Thomas

Zahn

2008

Conference Record of the 2008 IEEE International Symposium on Electrical Insulation

View full text Add to dashboard Cite

Paper insulated lead covered (PILC) cables have played an important role in underground power distribution for a hundred years. Replacing aged PILC before failure is critical to managing power distribution. Three prominent failure mechanisms accelerate cable aging: temperature stresses, moisture ingress, and partial discharge. The research focuses on the effect of temperature and moisture on the effective (complex) permittivity of the cable insulation. Measurements are performed using cylindrical dielectrometry sensors designed to be wrapped around the cable. The lead sheath of the cable is removed so that the sensors can be placed directly in contact with the insulation. From the measurements, the electrical properties of the material as a function of temperature and transient moisture diffusion are found.A theoretical treatment of the interdigital dielectrometry sensors with a cylindrical geometry is presented. Two classes of the geometry are studied. The φ periodic sensor geometry has electrodes aligned with the cylindrical axis and periodic around the circumference. The z periodic sensor geometry has the electrodes forming rings around the cylinder that are periodic along the cylindrical axis. The material is modeled by concentric rings of homogeneous materials. The electric field solution consists of an infinite summation of Fourier series terms. In finding the field solution and as a consequence of it, the potential, electric field lines, and the impedance between the driving and sensing electrodes are found. A generalized solution to the planar dielectrometry sensor topology is also presented. This solution allows for an arbitrary placement and excitation of electrodes, providing the analytical tools for a new generation of sensors.Dielectrometry sensors for use in φ and z periodic geometries are designed and manufactured on a 4 mil PTFE substrate. An experimental setup is designed and built to provide a temperature and humidity controlled environment for measurements. Special clamping mechanisms are used to secure the sensor to the sample. Custom built hardware is used to excite the sensor at frequencies ranging from 0.005 Hz to 10,000 Hz (over six decades), measure and record the response, and deliver it to a computer for storage and analysis.Steady state measurements are performed at temperatures ranging from room temperature to 100• C. Plastics, woods, and the PILC cable samples are measured. Using the theoretical model, the effective permittivity is estimated from the measurements. An Arrhenius temperature dependence is observed for several materials including the PILC cables. We characterize the temperature dependence of these materials by a master curve and activation energy. Together they give a complete description of the effective permittivity's frequency and temperature dependence.Transient measurements of moisture diffusion are made at constant temperatures for several 4 materials. For some experiments the boundary conditions limit the diffusion of moisture to one direction. When the z...

show abstract

“…The Electrical Capacitance Tomography (ECT) is one of the imaging system developed for monitoring and measurement of industrial processes [1][2][3][4][5][6]. The system has been extensively evaluated for applications in hydrocarbons multi-phase flow measurement and monitoring [7][8][9][10][11][12][13][14][15].…”

Section: Introductionmentioning

confidence: 99%

Comparative Performance Evaluation of Entropic Thresholding Algorithms Based on Shannon, Renyi and Tsallis Entropy Definitions for Electrical Capacitance Tomography Measurement Systems

Mwambela¹

2018

IJISA

View full text Add to dashboard Cite

Abstract-The concept of entropy as a measure of information has been extensively applied in information theory and related fields. The complex nature of information has resulted in some proposed entropy definitions. In image processing, the entropy concept has been used in developing thresholding techniques based on maximum entropy principles for image segmentation, enhancement and object detection purposes. In this article, entropy definitions are analysed to establish their relationship and after that evaluate their performance in image thresholding. Static simulated data from Electrical Capacitance Tomography measurement system for annular and stratified flows in multiphase hydrocarbons production has been used. Performance evaluation results of thresholding algorithms using Renyi entropy has shown to improve the measurements, particularly for stratified flow regimes. The improvement is solely based on the entropy definition, and it has been observed the introduced controlling parameters do not affect its performance. Renyi entropic thresholding algorithm is relatively robust as it is independent of the controlling parameter q and the grey level resolution. Therefore, there is the potential possibility of using Renyi entropic thresholding to improve measurements in hydrocarbons flow measurement using Electrical Capacitance Tomography measurement system.

show abstract

Electrical Capacitance Tomography—Sensor Models, Design, Simulations, and Experimental Verification

Cited by 106 publications

References 13 publications

Applications of Electrical Capacitance Tomography for Research on Phenomena Occurring in the Fluidised Bed Reactors

Applications of Electrical Capacitance Tomography for Research on Phenomena Occurring in the Fluidised Bed Reactors

Dielectrometry Measurements of Moisture Diffusion and Temperature Dynamics in Oil Impregnated Paper Insulated Electric Power Cables

Comparative Performance Evaluation of Entropic Thresholding Algorithms Based on Shannon, Renyi and Tsallis Entropy Definitions for Electrical Capacitance Tomography Measurement Systems

Contact Info

Product

Resources

About