A Novel Tomographic Flow Analysis System

Andrew Hunt1, John D Pendleton1 and Robert B White2

1 Tomoflow Ltd, West Hembury Farm, Askerswell, Dorchester DT2 9EN, UK, enquiries@tomoflow.com

2 CSIRO Minerals, Clayton, Australia

ABSTRACT

A novel flow analysis system is described which uses twin-plane tomographic data to derive detailed pictures of the velocity and concentration structure within complex two-phase flows. Initial results have been obtained using electrical capacitance tomography (ECT) but other modalities may also be used. By defining a set of contiguous zones over the flow cross-section the full integration of flowrate may be undertaken and a mass flowmeter created for two-phase systems. A number of flows have been analysed, and detailed results from selected tests are presented. The simplest experiments consist of solid particles dropped under gravity through a 5cm pipe and closely approximate the conditions at the exit of an industrial storage hopper. More complex flows were generated in a recirculating flow rig and are typical of conditions in an industrial pneumatic conveying line. The ECT flow analysis results can be used to explore the detail of complex structures and velocity fields while comparisons with computational fluid dynamics models, high-speed video and other measurements show that the ECT results are consistent and accurate to within a few per cent of the true value.

Keywords Multiphase Flow, Tomography, Velocity, Mass Flowmeter, Computational Fluid Dynamics