Research On ECT Three-dimensional Image Reconstruction Algorithm Based On Synthetic Plates

Electrical Capacitance Tomography(ECT)is a non-invasive,non-radiative,simple-structure industrial process tomography technology,which is applied to achieve the parameters detection of multi-phase flow in closed pipes and vessels based on electrical capacitance sensor.At present,two-dimensional ECT technology is relatively mature.However,the accurate three-dimensional information can not be obtained through two-dimensional imaging.Therefore,three-dimensional ECT technology is proposed to adapt to the need of industrial development.In recent years,the direct three-dimensional image reconstruction,as an branch of three-dimensional ECT technology,has been one of the research focuses in the field of electrical imaging.In this paper,we focus on the preliminary research of the ECT three-dimensional imaging technology based on synthetic plates,also called the Adaptive Electrical Capacitance Volume Tomography(AECVT)technology,which has been proposed in recent years.On the basis of previous work,the main work is as follows:1.Introduce the principle and research background of three-dimensional ECT reconstruction technology.The advantages of the AECVT sensor are analyzed by comparing the structure of the AECVT sensor with the ECVT sensor.2.A new AECVT sensitivity distribution calculation method based on electric field strength is proposed,which is based on the mathematical model AECVT sensitivity field and finite element simulation software.Compared with the traditional method of sensitivity distribution calculation,this method reduces the computation.The results show that sensitivity distribution calculated by this method conforms to the ECT sensitivity field distribution law.3.The three-dimensional image reconstruction of imaging objects based on ECVT sensor and AECVT sensor is compared by LBP algorithm and Landweber iterative algorithm.The simulation results show that the imaging results based on AECVT sensor are better under the same imaging objects condition.4.The sensitivity distribution of the AECVT sensor can be controled by adjusting the charge distribution of the small plates.In view of this characteristic,the influence of different voltage envelopes excitations on the image reconstruction of AECVT is discussed.The simulation results show that the multi-amplitude voltage excitation has the better reconstruction image than only single voltage excitation.The number of different amplitude voltages and changes of voltage position within the voltage envelope can also affect image reconstruction.The number of different amplitude voltages should not be too much,and the larger the amplitude distributed in the middle of the envelope,the better the image reconstruction quality is.Furthermore,the degree of influence of voltage amplitude and position change on reconstruction image quality is also related to the object,the more complex the object is,the more difficult to reconstruct.