A High Speed Current Pulse Electrical Resistance Tomography System for Dynamic Process Monitoring

Volume 1 ◽  
2004 ◽  
Author(s):  
E. W. Randall ◽  
A. J. Wilkinson ◽  
T. M. Long ◽  
A. Sutherland
Keyword(s):  
Current Pulse ◽  
Electrical Resistance ◽  
High Speed ◽  
Industrial Applications ◽  
Electrode System ◽  
Frame Rate ◽  
Manufacturing Cost ◽  
Electrical Resistance Tomography ◽  
Single Plane ◽  
Pulse Technique

This paper describes an instrument for Electrical Resistance Tomography (ERT) measurements based on a current pulse technique which has been shown by the authors to be a viable and easily implemented alternative to conventional AC excited systems. This system enables data to be acquired and recorded at 1000 frames/second on a single plane 16 electrode system and every 50th frame to be reconstructed and displayed to provide a real time display. The high frame rate enables transient phenomena to be investigated. The design incorporates a multiplexor allowing 8 rings of 16 electrodes to be sampled sequentially and thus provide data sets from all planes at 125 frames/second. This data can be processed to provide 3-D reconstructions and for velocity measurements using cross-correlation techniques. The system is primarily intended for use in minerals processing applications and data is presented from electrode systems used in slurry pipeline monitoring. It is suggested that simplified design and low manufacturing cost of the current pulse ERT systems will open the way for wide scale industrial applications.

Electrical resistance tomography using a bi-directional current pulse technique

2001 ◽  
Vol 12 (8) ◽  
pp. 997-1001 ◽  
Author(s):  
J J Cilliers ◽  
W Xie ◽  
S J Neethling ◽  
E W Randall ◽  
A J Wilkinson
Keyword(s):  
Current Pulse ◽  
Electrical Resistance ◽  
Electrical Resistance Tomography ◽  
Pulse Technique

Experimental Investigation of Volume Fraction in an Annulus Using Electrical Resistance Tomography

SPE Journal ◽  
2019 ◽  
Vol 24 (05) ◽  
pp. 1947-1956 ◽  
Author(s):  
Syed Raza Rehman ◽  
Alap Ali Zahid ◽  
Anwarul Hasan ◽  
Ibrahim Hassan ◽  
Mohammad A. Rahman ◽  
...  
Keyword(s):  
Multiphase Flow ◽  
Electrical Resistance ◽  
High Speed ◽  
Volume Fraction ◽  
Flow Behavior ◽  
Complex Flow ◽  
Flow Loop ◽  
Electrical Resistance Tomography ◽  
Horizontal Drilling ◽  
Hole Cleaning

Summary Horizontal drilling technology has shown to improve the production and cost–effectiveness of the well by generating multiple extraction points from a single vertical well. The efficiency of hole cleaning is reduced because of the solid–cuttings accumulation in the annulus in cases of extended–reach drilling. It is difficult to study the complex flow behavior in a drilling annulus using the existing visualization techniques. In this study, experiments were carried out in the multiphase flow–loop system consisting of a simulated drilling annulus using electrical resistance tomography (ERT) and a high–speed camera. Real–time tomographic images (quantitative visualization) of multiphase flow from ERT were compared to the actual photographs of the flow conditions in a drilling annulus. The quantitative analysis demonstrates that ERT has a wide potential application in studying the hole–cleaning issues in the drilling industry.

scholarly journals Investigation of Multi-Plane Scheme for Compensation of Fringe Effect of Electrical Resistance Tomography Sensor

Sensors ◽  
2019 ◽  
Vol 19 (14) ◽  
pp. 3132 ◽  
Author(s):  
Wenbin Tian ◽  
Xiaofeng Liang ◽  
Xiaolei Qu ◽  
Jiangtao Sun ◽  
Shuo Gao ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
Electrical Resistance Tomography ◽  
Cross Sectional ◽  
Single Plane ◽  
Measurement Plane ◽  
3D Sensing ◽  
Simulation Results ◽  
Multiple Plane ◽  
Fringe Effect ◽  
Plane Scheme

Conventional electrical resistance tomography (ERT) sensors suffer from the fringe effect, i.e., severe distortion of the electric field on both ends of the measurement electrodes, leading to a 3D sensing region for a 2D sensor. As a result, the objects outside an ERT sensor plane affect the sensing and hence image, i.e., deteriorating the image quality. To address this issue, a multiple-plane ERT sensor scheme is proposed in this paper. With this scheme, auxiliary sensor planes are used to provide references for the fringe effect of the measurement plane, for compensation by subtracting the weighed influence of the fringe effect. Simulation results show that the proposed scheme, either three-plane or two-plane sensor, can compensate for the fringe effect induced by objects outside the measurement plane with a variety of axial object distributions, i.e., several non-conductive bars or conductive bars placed at different cross-sectional and axial positions inside the sensor. Experiments were carried out. Images obtained with single-plane and multiple-plane ERT sensors are compared, and the proposed compensation scheme has been hence verified.

scholarly journals Electrical Resistance Tomography for Control Applications: Quantitative Study of the Gas-Liquid Distribution inside A Cyclone

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6069
Author(s):  
Muhammad Awais Sattar ◽  
Matheus Martinez Garcia ◽  
Robert Banasiak ◽  
Luis M. Portela ◽  
Laurent Babout
Keyword(s):  
Electrical Resistance ◽  
High Speed ◽  
Correction Method ◽  
Electrical Resistance Tomography ◽  
Separation Processes ◽  
Liquid Distribution ◽  
Core Diameter ◽  
Ill Posed ◽  
Inlet Conditions ◽  
And Control

Phase separation based centrifugal forces is effective, and thus widely explored by the process industry. In an inline swirl separator, a core of the light phase is formed in the center of the device and captured further downstream. Given the inlet conditions, this gas core created varies in shape and size. To predict the separation behavior and control the process in an optimal way, the gas core diameter should be measured with the minimum possible intrusiveness. Process tomography techniques such as electrical resistance tomography (ERT) allows us to measure the gas core diameter in a fast and non-intrusive way. Due to the soft-field nature and ill-posed problem in solving the inverse problem, especially in the area of low spatial resolution, the reconstructed images often overestimate the diameter of the object under consideration leading to unreliable measurements. To use ERT measurements as an input for the controller, the estimated diameters should be corrected based on secondary measurements, e.g., optical techniques such as high-speed cameras. In this context, image processing and image analysis techniques were adapted to compare the diameter calculated by an ERT system and a fast camera. In this paper, a correction method is introduced to correct the diameter obtained by ERT based on static measurements. The proposed method reduced the ERT error of dynamic measurements of the gas core size from over 300% to below 20%, making it a reliable sensing technique for controlled separation processes.

scholarly journals Limited Angle Electrical Resistance Tomography in Wastewater Monitoring

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1899 ◽  
Author(s):  
Chenning Wu ◽  
Martin Hutton ◽  
Manuchehr Soleimani
Keyword(s):  
Electrical Resistance ◽  
High Speed ◽  
Low Cost ◽  
Radiation Hazard ◽  
Reconstruction Method ◽  
Limited Data ◽  
Electrical Resistance Tomography ◽  
Limited Region ◽  
Image Reconstruction Method ◽  
High Speed Design

Electrical resistance tomography (ERT) has been investigated in monitoring conductive flows due to its high speed, non-intrusive and no radiation hazard advantages. Recently, we have developed an ERT system for the novel application of smart wastewater metering. The dedicated low cost and high-speed design of the reported ERT device allows for imaging pipes with different flow constituents and monitoring the sewer networks. This work extends the capability of such a system to work with partially filled lateral pipes where the incomplete data issue arises due to the electrodes losing contact with the conductive medium. Although the ERT for such a limited region has been developed for many years, there is no study on imaging content within these limited regions. For wastewater monitoring, this means imaging the wastewater and solid inclusions at the same time. This paper has presented a modified ERT system that has the capacity to image inclusions within the conductive region using limited data. We have adjusted the ERT hardware to register the information of the non-contact electrodes and hence the valid measurements. A limited region image reconstruction method based on Jacobian reformulation is applied to gain robustness when it comes to inclusion recovery in limited data ERT. Both simulation and experimental results have demonstrated an enhanced performance brought by the limited region method in comparison to the global reconstruction.

Front-End Circuit in Electrical Resistance Tomography (ERT) for Two-Phase Liquid and Gas Imaging

2014 ◽  
Vol 70 (3) ◽  
Author(s):  
F. R. Mohd Yunus ◽  
R. Abdul Rahim ◽  
Suzanna Ridzuan Aw ◽  
N. M. Nor Ayob ◽  
M. P. Jayasuman ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
High Speed ◽  
Low Cost ◽  
Bubble Radius ◽  
Current Source ◽  
Electrical Resistance Tomography ◽  
Two Phase ◽  
2D Simulation ◽  
Phase Liquid ◽  
Frequency Changes

A steady and precise Voltage Control Current Source (VCCS ) with broad bandwidth plays a very important role in the quality of final images for the Electrical Resistance Tomography (ERT) system. Therefore, a model of current source is proposed in the paper which implement advanced Howland current pump as VCCS. The model are simulated through a software named multisim, and the simulation results show the proposed high-speed operational amplifier (op-amp) LM7171 is capable to produce constant output current at 10 mA (peak) when the frequency changes between 1 kHz to 500 kHz with load varies from 10 Ω to 1 kΩ. A two-dimensional (2D) simulation was performed using COMSOL and the results showed that the model is capable to detect air bubble (radius=10 mm) in a two-phase liquid and gas. The result presented with opposite excitation method with 150 kHz current at 10 mA. The measurement of boundary potentials are significantly influenced by bubble positions particularly towards the boundary. They are hoped to provide useful approaches for the design of practical and low-cost VCCS in ERT system.

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