Study On Software And Image Reconstruction Algorithms For Wire Mesh Tomography System

Wire Mesh tomography technology is one of these hot problems on the holdup measurement of two-phase flow in recent years. Compared to the traditional process tomography, Wire Mesh tomography technology adopted intrusive measuring method. Because it possesses instant flow imaging effects, so it can get higher precision than traditional no-intrusive tomography in holdup measurement in two-phase flow.At present, Wire Mesh tomography technology has been studied and developped in flow characteristic parameter measurement of two-phase flow gradually. This paper will pay great emphasis on the in-depth study on Wire Mesh tomography technology through system software, image reconstruction algorithms and finite element simulation of electric field distribution in simplified model. The main conclusions of this paper are as follows.1. In the design of software for Wire Mesh tomography technology, here we use Microsoft Visual C++ 6.0 development environment to design a set of software for Wire Mesh tomography technology base on 32-bits Windows platform. The tomography software can be divided into some modules as follows: serial communication module; five kinds of image reconstruction algorithms module; data saving and replaying module; image and data displaying module. We also use multithread to improve the real-time of image reconstruction.2. In the study of image reconstruction algorithms, because Wire Mesh tomography technology directs at the measurement of some points in flow cross-section, so we need to use interpolation algorithms if we want to get complete image of flow cross-section. In this paper, we use five kinds of algorithms, such as nearest neighbor algorithm, average interpolation algorithm, bilinearinterpolation, bicubicinterpolation and inverse distance square weighting method to do image reconstruction. By comparing these five algorithms, we find bilinearinterpolation and inverse distance square weighting method are more close to the desired two-phase flow image, and the maximum spatial resolution can be increased from 16×16 to 64×64.3. In the finite element simulation of electric field distribution in simplified model, through finite element simulation of electric field distribution in simplified model, we compare the different diameters and space between the planes of transmitter electrodes and receiver electrodes that can give some guides in sensor processing and design.