Characteristic Analysis And Simulation Of Sensitive Field For Electrical Resistance Tomography System

With process tomography technique, multiphase flow two-dimensional or three-dimensional space-time partial and microscopic distribution information can be obtained in multiphase flow parameter measurement, which provides an effective approach in solving the difficulty of multiphase flow parameter measurement. Process tomography technique has made a great progress in the last ten years. According to the way of acquiring information and principle of sensor, process tomography technique can be divided into more than ten kinds such as electrical capacitance tomography, electrical resistance tomography, electromagnetic tomography and so on. The subject investigated in this dissertation is electrical resistance tomography system, which is on the basis of resistance sensor principle. Some relative problems such as system modeling with finite element method, analysis and calculation for sensitivity field, influence generated by the different flow regimes on the sensitivity field distribution are discussed.The important meaning of multiphase flow measurement to the science research and industry production is summarized, at the same time main parameter, current status and developing trend of multiphase flow measurement technique are analyzed. In addition, the structure and technique characteristic of electrical resistance tomography system is clarified. The current status and broad industrial application prospect of electrical resistance tomography are discussed. The key problems that must be solved in the development of electrical resistance tomography are also pointed out. It is emphasized that the soft field characteristic and the low resolution of image reconstruction are the main problems that result in the difficulty of its practical application. Compared with other numerical analysis methods, the finite element method is adopted to solve the problem, and the necessity of which is discussed. The system of finite element is built, and it can calculate numerical value of sensitivity field. The experiments show that the finite element model is feasible, which provides the basis for related image reconstruction algorithms. And the research of the sensitivity field distribution can be started with uniformity field and non-uniformity field, and emphasize to analyze the soft field characteristic according to flow regimes, which is that distribution of the medium can influence the distribution of the sensitivity field. Finally the finite element simulation software of electrical resistance tomography system is developed, whose interface is simple and utility. It is easier to analyze field, which is difficult to acquire theoretic value. Also, the software promotes the other following research to study.