New capacitively coupled electrical resistance tomography (CCERT) system

摘要

This work focuses on the hardware improvement of a CCERT system. An inductor module is developed by the simulated inductor technique. With the inductive reactance of the developed inductor module, the capacitive reactance of the coupling capacitances is eliminated by the impedance elimination principle and the unfavorable influences of the coupling capacitances are overcome. The digital phase-sensitive demodulation technique is introduced to obtain the total impedance of gas-liquid two-phase flow, including the real part, the imaginary part and the amplitude. Finally, a new CCERT system prototype is developed. Impedance measurement experiments and practical image reconstruction experiments are conducted. The research results show that the design of the new CCERT system is successful. The unfavorable influences of the coupling capacitances are effectively overcome and the signal-to-noise ratio of the new system is improved. Compared with the previous CCERT system, the accuracy of the impedance measurement and the quality of image reconstruction of the new system are improved. Meanwhile, the new CCERT system can also obtain the total impedance of gas- liquid two-phase flow.