Optimum Design Of ECT/ERT Dual-modality Electrode Array And Study On The Forward Problem

As a kind of nondestructive and visible measurement techniques, electrical tomography has found many important applications in both industrial and medical areas, for its low cost, fast response, harmless and non-invasive.Electrical Capacitance Tomography(ECT) and Electrical Resistance Tomography (ERT) are the two most developed PT techniques based on the theory of Electric-magnetic field nowadays. ERT is suitable to measure two-phase flow in which conductive medium is taken as continuous phase, while ECT is suitable to measure two-phase flow in which non-conductive medium is taken as continuous phase.In order to analyze the measurement mechanism of electrical tomography in depth,optimum design of ECT/ERT dual-modality sensing electrode array and the simulation of ECT/ERT are studied in this dissertation.Firstly, using COMSOL simulating software, the 3D ECT/ERT electrode array for simulation is established. Based on this model, the'soft-field'effect in which the sensing field is affected by the component distribution of the object is considered and the effect of sensing electrode array geometrical shape and architecture parameters on sensitivity response is analyzed.Secondly, sensing electrode array model of 3-Dimensional ECT/ERT dual modality is established by using the software COMSOL. According to the uniformity of sensitivity field distribution, the correlation coefficient and the reconstructed image space resolution, the ECT/ERT dual modality sensing electrode arrays are optimized.Thirdly, the customized user interfaces for ERT and ECT simulation have been designed using COMSOL Script. The customized user interfaces bring obvious improvement in display effect of the process of simulation and make the process state visible and clear.Finally, According to CT scanning of head and pulmonary, the head and pulmonary model of human are established. Combining with the prior information of the conductivity contribution information of human tissue and organ, the simulation of Electrical Impedance Tomography based on head and pulmonary is studied using conjugate gradient method.