GOALI: Examination of Gas-Solid Multiphase Flow Dynamics Using Electrical Impedance Tomography

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

Abstract The proposal is motivated by the current need to better understand those industrial processes dominated by the flow of gas-solid mixtures .The attendant property measurement of these unsteady, three-dimensional flows precludes their sampling, since solid probes would disturb the phenomena of interest (the formation or destruction of clusters, for instance). There has been some success, however, in using remote sensing tomography: in such a technique, the cumulative interference of many beams with the matter inside a flow container, can be reconstructed mathematically into a three-dimensional time-resolved map of local properties. The PI proposes the "electrical impedance tomography", in which a number of electrodes are mounted around the volume of interest, and a prescribed current is applied to them. It is then possible to infer from the exiting voltages the spatial distribution of impedance inside the volume. The phase distribution map (liquid-gas, solid-gas) can be extracted from this data by classical electromagnetic theory. Specifically, the PI proposes to develop and test a solid-gas tomographic technique, where both space and time resolution will be achieved. The field covered by 48 electrodes will be strongly three dimensional (1128 independent projections), and the resolution will be boosted by using multiple frequency excitation, where 12 lock-in amplifiers will collect an order of magnitude more data in the same time interval. The goal is "to collect a complete data set within 10 milliseconds". In this fashion, the PI is confident that he will be able to " examine cluster formation and bulk flow dynamics, and near wall particle dynamics".