Abstract:In order to reduce the nonlinear and ill-posed inverse problem of electrical capacitance tomography (ECT), one kind of exciting-measuring mode is presented for ECT sensor consisting of 24 segments linked in 8 groups, treated as single, extremely broad electrodes forming 8-electrode sensor. The values and the dynamic range of measured capacitance data, the uniformity of sensitivity distribution and the reconstructed images of different flow regimes were compared with conventional exciting-measuring mode 12-electrode sensor. Two kinds of sensors were simulated by utilizing COMSOL and Matlab software. The simulation results showed that for the presented exciting-measuring mode, the number of independent measurements close to that of 12-electrode sensor, which will not cause the decrease of real-time reconstruction speed. However, the measured capacitance valves are larger and its dynamic range is smaller, which can reduce the difficulty of measurement circuit. Meanwhile, the sensitivity distribution is more uniform and the quality of reconstructed images for the objects in the central locations is improved obviously.
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