An adaptive multi­modality (ECT, ERT and electro­dynamic) sensor for multiphase flow measurement

Xiang Deng

School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University Beijing 100044, China, xiangdeng@263.net

Dixiang Chen

School of Mechatronics Engineering and Automation, National University of Defence Technology Changsha 410073, China, chendixiang@163.com

Wuqiang Yang

School of Electrical and Electronic Engineering, The University of Manchester Manchester M60 1QD, UK, w.yang@manchester.ac.uk

ABSTRACT

Accurate measurement of multiphase flows, including gas/solids, gas/liquid and liquid/liquid flows, is still challenging. In principle, electrical capacitance tomography (ECT) can be used to measure the concentration of solids in a gas/solids flow and the liquid (e.g. oil) fraction in a gas/liquid flow if the liquid is non­conductive. Electrical resistance tomography (ERT) can be used to measure a gas/liquid flow if the liquid is conductive. It has been attempted to use a dual­modality ECT/ERT system to measure both the concentration profile and the velocity profile by pixel­based cross correlation. However, this approach is not realistic because of the dynamic characteristics and the complexity of multiphase flows and the difficulties in determining the velocities by cross correlation. In this paper, the issues with dual modality ECT/ERT and the difficulties with pixel­based cross correlation will be discussed. A new adaptive multi­modality (ECT, ERT and electro­dynamic) sensor, which can be used to measure a gas/solids or gas/liquid flow, will be described. Some details of the electrostatic charge amplifier and signal processing will be discussed. Initial experimental results will be given.

Keywords Multi­modality sensor, ECT, ERT, Electro­dynamic, Multiphase flow measurement