Research On The Key Techniques In Eight Electrodes Electrical Capacitance Tomography System

Flow imaging is a new technique delevoped rapidly in recent years, which has great developmental potential and wide industial application prospect. Having many distinct advantages such as low cost, wide application field, simple structure, non-invade and better safety, Electrical Capacitance Tomography(ECT) has being the most popular research direction and the main development in flow imaging technique. There is still a lot of work to be done before practical use of the technique.The object of this dissertation is on the research of 8-electrode Electrical Capacitance Tomography system. The topics studied are: analyse and computation of sensitivity field, optimal design of transducer, identification of the pattern of two-phase flow, image reconstruction of the discrete phase distribution, concentration measurement. The main problems researched in the dissertation and achievements are as follows:1. On the base of flowing imaging technic and oil-water Two-phase flow detection system, character, category and important parameters of the multi-phase flow is analyzed and induced. It is pointed out that multi-phase flow parameter detection is very important for research and industry production.2. The principle of the capacitance tomography and structure of the system are analysed, and basic characters and status in quo areintroduced.3. The mathematical model of the sensitivity field is given.4. The optimal design of transducer is done and the performance of the transducer is improved.5. Identification of the pattern of two-phase flow is studied. A mathematical model of image reconstruction of flow pattern identification is proposed. A suitable algorithms of flow pattern tomography and a algorithm of flow pattern identification are created. The experiment proved that the model is dependable and the accuracy of the algorithm is enough.