Research On Image Reconstruction Algorithm Based On Soft-field Characteristics For Electrical Capacitance Tomography

Electrical capacitance tomography (ECT) system is a recently developed new technology. It has advantages of non-invasive, no radiation, simple structure and cheap price, etc. Because of these benefits, ECT has been found many broad applications in detecting multi-phase issue. However, now some distance away from the actual application, further research and development needs to be done.In the paper, 12-electrode capacitance tomography system was researched,mainly involving the analysis of the sensitive field of ECT based on finite element method and comparison of all sorts of image imaging algorithms. Conjugate gradient algorithm was improved, while tabu search algorithm was introduced into the annualautocatalyst output image reconstruction, which got a good effect. The value of further research is promising.The study we have done is as follows:1. This paper introduces the development of the computer tomographic imaging status and the development space of the capacitance tomography as well as the prospect of broad application in industry, which Points out the importance of ECT non-destructive testing for research industrial production, and analyzes and summaries the direction and the trend of development of the future ECT testing.2. This paper introduces the composition and working principle of the ECT system, and analyzes the establishment of a mathematical model of ECT system and the reconstruction principle of the sensitivity field image.3. The use of finite element method analysises and simulates the system of the ECT, and improves finite element through the Galerkin method. So the solution accuracy and speed of finite element have been extremely improved, which provides good transcendental data for the image reconstruction.4. Through the analysis and comparison of all sorts of image imaging algorithm of ECT and the improvement of the conjugate gradient algorithm, a new conjugate gradient algorithm based on trust region was proposed, whose the imaging quality and speed have improved considerably than the conjugate gradient algorithm.5. The taboo search algorithm is introduced into the image reconstruction of ECT in the last, which designs reasonably by virtue of parameters of taboo search method ,and make reconstructed image improvement .