| Process Tomography (PT) techniques, which has been development rapidly in recent several ten years, have made certain progress in field of measurement of two-phase flow/multiphase flow parameter's distribution status. It might become a means for two-phase flow measurement and could be widely applied in industry.Electrical Capacitance Tomography (ECT) is one of the techniques of PT, which is widely researched. It has low-cost, high-speed, robust and non-intrusive.In base of the original design, make a great effort to the following questions:1. Put forward to a new simplified circuit of mode selection, it seemed that the new way is more visible, and the number of chip is reduced. Programmed by Verilog HDL, and the verification result shows that the above amend is complete correct.2. In stead of the traditional phase shift circuit, PLL is used to realize accurately track to frequency and phase, and eliminate the influence of stray capacitance.3. DSP is used to realize the algorithm of image reconstruction, and then design the whole circuit which is connect to DSP.4. Use assembler language to program and debug the algorithm, and then, calculate that the realized time is 0.748 ms .5. Simulate the sensitive field in the pipe, provide sensitivity matrix for image reconstruction.6. Put forward to a new algorithm of image reconstruction which is base on minimum two multiplication and SIRT iterative technique.7. Use ANS YS simulated data to verify the result of image reconstruction, result shows that the new algorithm has high precision.
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