用于油气两相流空隙率测量的电容层析成像量化新算法研究

Study on algorithm of electrical capacitance tomography for voidage measurement of gas-oil two-phase flow

提出了一种基于Tikhonov正则化原理并组合同步迭代算法(simultaneous reconstruction technique,SIRT)的组合型量化图像重建新算法,Tikhonov正则化原理用于克服图像重建中的不适定性问题并得到初始重建图像,SIRT算法用于对初始图像的迭代改善从而得到最终重建图像.新算法图像重建的质量优于目前常用的滤波线性反投影(FLBP)算法.将新算法应用于油气两相流的空隙率测量表明,提出的量化新算法是有效的.并经实验验证,空隙率测量的最大误差可小于5%,测量时间小于0.25s.

A hybrid image reconstruction algorithm which combined the Tikhonov regularization theory with the SIRT (Simultaneous Reconstruction Technique) algorithm was presented. The Tikhonov regularization theory was used to solve the ill-posed problem of image reconstruction and the SIRT algorithm was used to improve the quality of the final reconstructed image. Compared with the filter linear back projection algorithm (FLBP), the quality of reconstructed image by the hybrid image reconstruction algorithm was improved. Based on the algorithm, some experiments of global voidage measurement of gas-liquid two-phase flow were carried out. The total measurement time is less than 0.25 second and the maximum error of voidage measurement is less than 5%, which show the effectiveness of the proposed reconstruction algorithm.