Electrical Capacitance Tomography (ECT) is one of the soft field tomography that widely used for the purpose of measurement and monitoring of multiphase flow. Common problem of the soft field tomography is low quality and unstable images in the pipe especially at the center section of the pipe. In this paper, an ECT system with a comparison between common approach and a parallel approach is presented. Simulation in 2 dimensions with 16-electrode is carried out to observe a potential projection. The COMSOL Multiphysics software is used to investigate the state and response of the electric field with this approach by exporting data with 128x128 pixels. Air bubbles as a phantom in the oil medium have been tested and analyzed. Linear Back-Projection Algorithm (LBP) is implemented using MATLAB software to obtain a tomogram. A Multi Scale Structural Similarity, MSSIM was applied to compare both approaches. Consequently, the resolution and quality of the pictures in the pipes can be distinguished. However, a further investigation is needed to improve the parallel approach for ECT system.

This paper presents the effect on potential distributions and current streamlines for Electrical Resistance Tomography (ERT) applying metal wall pipe. A conducting boundary approach was applied in the measurement part of the research and COMSOL Multiphysics software has been applied in this work to solve the forward problem of the system. Sixteen electrodes with gold plated material as the conducting surface and FR4 as the insulating material were implemented as the sensing plate in the research. The simulations showed that the sensing field will be deflected based on the conductivity distribution within its sensing region. The electrical potential of the system also varied accordingly.

The paper aims to investigate the possibility of an invasive method for electrical capacitance tomography system for steel pipe application. This work presents the development process for modeling an ECT (Electrical Capacitance Tomography) sensor using COMSOL Multiphysics. COMSOL Multiphysics software is implemented as the main tool to model the ECT system. The 12 electrodes are modeled in 2-dimensional and it is based on the invasive approach. The ECT system is developed to obtain the electrical potential distribution between electrodes when an electric field is applied. Besides, it also obtains the permittivity distribution inside the closed pipe. This invasive approach is applied for the steel pipe that cannot be used with common ECT. Several positions of bubble air as the obstacle in the oil medium are tested. As a result, the sensor readings performance inside the region of interest is analyzed. Simultaneously, the tomograms are also obtained and analyzed using MATLAB software. A linear back-projection algorithm is implemented to reconstruct the image of the region of interest. Thus, the possibility of the ECT system applied for steel pipe can be observed and compared when there is a change of readings between the full oil and the existing obstacle inside the steel pipe. Besides, the tomograms for each condition tested can be observed. In short, the invasive approach for ECT is seen to be possible to apply for oil-gas application in steel pipe. The LBP algorithm with the average MSSIM value around 0.3 was able to detect the oil-gas regime inside the steel pipe.

Electrical resistance tomography (ERT) is a widely used in geophysical application. The purpose of this paper is to investigate the possibility of ERT systems to detect leakage or cracking of houehold underground pipe. A COMSOL Multiphysics software is implemented as the main tool for modelling ERT systems. 8 electrodes were modelled in 2 dimensions. At the same time, tomograms were also obtained and analyzed using MATLAB software. A linear back projection algorithm is implemented to reconstruct the image of the attractive area. Several different size and positions of underground leaking were analysed. The average value of MSSIM for all results in 0.01. This is because the smearing effect occurred when the linear back projection was implemented. In summary, a non-invasive strategy based on ERT is projected to be deployed for detecting leaks or cracks in underground pipes, but more research is required.

This paper presents a hardware design, arrangement and measurement for optical tomography where optical tomography uses light sources as the transmitter and photodiodes as the receiver. By using parallel projection for 44 laser transmitters and photodiode receivers at the cross-sectional boundary, the existence of bubbles inside a vertical column pipeline is determined. Octagon modelling with an eight-sided jig is used for projection and the measurement method for this research is shown. An offline technique is used to collect readings from each signal and the image is reconstructed from the data received.

Industrial process pipelines are mostly known to be constructed from metal which is a conducting material. Bubbles or gas detection are crucial in facilitating the bubble columns performance. By employing the Electrical Resistance Tomography (ERT) technique, a simulation study using COMSOL has been conducted to investigate the effect of excitation strategy, bubble sizes and locations towards the metal wall system. As for the current excitation strategy, conducting boundary protocol has to be applied when it comes to metallic vessel to overcome the grounding effect. Bubbles with a greater size than 2 mm and especially the one that is located near the wall boundary are much easier to detect. Further potential improvements to the current design and image reconstruction of the ERT system are desirable to improve the detection of small and centred bubble.