两相流电容层析成像中图像重建的研究

Research on Technology of Image Reconstruction in Two-phase Flow ECT

电容层析成像(Electrical Capacitance Tomography,ECT)技术是目前最具发展前景的多相流参数检测方法,它可重建两相流在其流经管道横截面上的分布图像。对12电极的电容传感器进行了数学描述,建立了电容敏感场分布的数学模型及其有限元模型,分析了敏感场的算法,利用有限元法实现了敏感场的仿真,并且研究了敏感场分布的规律。在此基础上利用灰度图像重建的方法重现出不同流体分布状态下油管横截面的灰度图像,为两相流在线检测仪器的设计提供了理论依据。

The electrical capacitance tomography （ECT） system is known as the best measuring method at present. It can reconstruct cross-sectional phase distribution images of the pipeline through which two-phase flow runs. After proposing the mathematical formulation of capacitance transducers, the paper built the mathematical and finite element model of the capacitance sensitivity field distribution respectively of 12 electrode ECT system. Furthermore, it analyzed the theory and the constitution of ECT system and the computing method of the sensitivity field. Then it realized the simulation of the sensitivity field and studied the rules of the distribution of the sensitivity field by FEM. Based on the sensitivity field, the reconstruction image of ECT was eventually got by the gray image reconstruction method, which provided the theoretical base for online two-phase flow detector.