Electrical Capacitance Tomography--from Principles to Applications
Among various industrial tomography modalities, electrical capacitance tomography (ECT) is the most mature and has been used for many challenging applications. ECT is based on measuring very small capacitance from a multi-electrode sensor and reconstructing the permittivity distribution in a cross section of an industrial process. Compared with other tomography modalities, ECT has several advantages: no radioactive, fast response, both non-intrusive and non-invasive, withstanding high temperature and high pressure and of low-cost. Because of very small capacitance to be measured (much smaller than 1 pF) and the “soft-field” nature, ECT does present challenges in capacitance measurement and solving the inverse problem. The latest AC-based ECT system can generate online images typically at 100 frames per second with a signal-to-noise ratio (SNR) of 73 dB. Examples of industrial applications include gas/oil/water flows, wet gas separation, pneumatic conveyors, cyclone separators, pharmaceutical fluidised beds, and clean use of coal by circulating fluidised bed combustion and methanol-to-olefins conversion. During this tutorial, ECT is discussed from principle to industrial applications, together with demonstration of an AC-based ECT system.
Wuqiang Yang graduated from Tsinghua University. Since 1991, he has been working with UMIST and The University of Manchester in the UK. He became Professor of Electronic Instrumentation in the Dept. of Electrical and Electronic Engineering in 2005. His main research interests include industrial tomography, especially electrical capacitance tomography (ECT), sensing and data acquisition systems, circuit design, image reconstruction algorithms, instrumentation and multiphase flow measurement. He has published 400 papers with an h-index of 45. He is an Associate Editor of IEEE Trans. IM, editorial board member of 6 other journals (including Meas. Sci. Technol.), guest editor of many journal special issues, referee for more than 50 journals and visiting professor at several other universities. He has two books published: “Sensor Array” by InTech and “Imaging Sensor Technologies and Applications” by IET. He received several national awards, including the 1997 IEE/NPL Wheatstone Measurement Prize. He was an IEEE Distinguished Lecturer from 2010 to 2016, Vice Chair of I2MTC 2017, and one of key organisers of IEEE International Conference on Imaging System and Techniques for many years. His biography has been included in Who’s Who in the World since 2002.
Publication Year: 2020