Evaluation of an Electromagnetic Flow Tomography System With Multiple Pairs of Field Coils

In this contribution, we propose a new sensor design for the measurement of velocity distributions in pipe flows with electromagnetic flow tomography. The developed sensor consists of two parallel rings of field coils on the surface of the measuring pipe. The coils are arranged in close proximity to the electrodes and enclosed in two magnetic circuits to minimize the excitation current and coil size. We developed a measurement system for the new sensor design using 12 electrodes and 12 pairs of field coils and we implemented a reconstruction algorithm to obtain the flow velocity distribution. Two different excitation schemes for a quasi-homogeneous and a localized magnetic field were evaluated. After performing a calibration using simulated electrode voltages, the functionality of the sensor is verified with two different flow profiles: a rotationally symmetric and an asymmetric flow profile.