Electrical impedance tomography and new insights

An algorithm for 2D-EIT created in MATLAB^® is introduced and described in [2, chap. 5], which is used to improve the quality of the cross-sectional reconstructions and to increase the temporal resolution of the method by one order of magnitude.

The different behavior of an electrical potential in two-dimensional and three-dimensional case is exploited. The idea is first tested and verified by experimental data. The new measuring system “Sciospec EIT 16” from Sciospec Scientific Instruments GmbH is used for measurements. For a possible use in teaching the algorithms-source texts are slim and are available to the public.

The results presented could be used for industry, e.g. in the field of application of extrusion methods for monitoring melting or mixing processes.

New method – Bridge between 2D and 3D

Examination object: 28cm and 10cm diameter pipe water column, anomaly: insulator cylinder of height 28cm and 3cm diameter; Current frequency: 20 kHz; Framerate: 1 / s; Excitation by any two adjacent electrodes; Number of excitation patterns g: 16; Number of measurements per frame: 16 x 16; Reconstruction variable: electrical conductivity in S / m; Notation: u2 {Measurement data at 1 cm water level without anomaly; Corresponds approximately to a 2D problem; U3 {Measurement data at water level of 28 cm without anomaly; Corresponds approximately to a 3D problem; ~ U3: Measurement data at water level of 28 cm with anomaly; T (~ u3): Transformed measured data, input data for the 2D reconstruction algorithm; F2: Solver of the direct problem