Development on 3D electrical capacitance tomography instrument

An Electrical capacitance tomography (ECT) system include its sensor, measuring circuit and image reconstruction algorithm is described in this paper. An AC-based capacitance circuit is introduced because it is stray-immune and small capacitance can be measured. The 3-D image is reconstructed from a set of 2-D images which are reconstructed from an optimization iterative reconstruction algorithm. The 3D ECT instrument is used to observe distribution of discrete phase of two-phase flow in closed pipe. The preliminary experimental results demonstrate the distribution of discrete phase of two-phase flow is observed easily. The ECT system has advantage as regards two-phase flow visual monitoring.