A software tool that facilitates the development of image reconstruction algorithms, and the design of optimal capacitance sensors for a capacitance-based 12-electrode tomographic flow imaging system are described. The core of this software tool is the finite element (FE) model of the sensor, which is implemented in OCCAM-2 language and run on the Inmos T800 transputers. Using the system model, the in-depth study of the capacitance sensing fields and the generation of flow model data are made possible, which assists, in a systematic approach, the design of an improved image-reconstruction algorithm. This algorithm is implemented on a network of transputers to achieve a real-time performance. It is found that the selection of the geometric parameters of a 12-electrode sensor has significant effects on the sensitivity distributions of the capacitance fields and on the linearity of the capacitance data. As a consequence, the fidelity of the reconstructed images are affected. Optimal sensor designs can, therefore, be provided, by accommodating these effects.

The problem of how to accurately measure the flowrate of oil–gas–water mixtures in a pipeline remains one of the key challenges in the petroleum industry. This paper discusses why three-phase flow measurement is still important and why it remains a difficult problem to solve. The measurement strategies and principal base technologies currently used by commercial manufacturers are described, and research developments that could influence future flowmeter design are considered. Finally, future issues, which will need to be addressed by manufacturers and users of three-phase flowmeters, are discussed.

The problem of how to meter oil-water-gas mixtures has been a significant one in the oil industry since the early 1980s. Since then, considerable research has been conducted into the development of a three-phase flowmeter suitable for use in an offshore environment. This work discusses why three-phase flow measurement is important, the principal strategies and technologies which may be used to meter three-phase flows, and reviews the status of some currently available solutions.Richard Thorn obtained a PhD from Bradford University in 1979 for work on cross-correlation flow measurement, and is currently a Senior Lecturer in the Department of Fluid Engineering and Instrumentation at Cranfield University. Previous to this he was at Chr Michelsen Institute, Bergen, and then the School of Electronic Engineering, University of South Australia. He has co-authored three books and many papers on measurement science and instrumentation. His main research interests are the development of multiphase instrumentation and the structured design of measurement systems.