An ECT System And Data Processing Based On DSP

Multiphase flow system is a complex, nonlinear system. There are interface effect and relative velocity between these multiphase flow. That causes the difficult of measurement of multiphase flow. In the world, the multiphase flow is an exploration research field, which is waited to develop urgently. Process Tomography (PT) technique, which is has been developed rapidly in recent ten years, has great developmental potential and wide industrial application prospect. Electrical Capacitance Tomography (ECT) has many distinct advantages such as low cost, wide application field, simple structure, non-invasive measurement and better safety, ECT has being the most popular research direction and the main development in process tomography 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 16-electrode Electrical Capacitance Tomography system. The main topic is data acquisition, image reconstruction. The main works are as follows:1. The paper introduces the basic principles of tomography, the system constitution, the basic features, developing status and the process tomography based on various sensing technique. It also analyzes the principle and proposes the mathematical model of sensitivity field, discusses the peculiar advantages and research status of the technique.2. Designed a relevant data collection system of ECT system.3. A DSP based data acquiring system has been developed, which can communicate with upper computer expediently and fleetly in real time, also advance the speed of data acquisition and processing.4. The main software of DSP has been designed and debugged. Using assembler language to program and debug the algorithm, it greatly improves the speed of image reconstruction.5. The process of simulating the sensitive field on ECT system has been introduced. Several image reconstruction algorithms on ECT technique are compared and analyzed.6. To obtain the high quality image of discrete phase distribution, the paper puts forward a new algorithm of image reconstruction, which is based on minimum two multiplications and SIRT iterative technique. The experimental results show that the model is reliable, the accuracy of algorithm is higher, the reconstructed image accords with the actual situation, and the quality of reconstructed image is improved.