Image Reconstruction Technology for Voidage Measurement in Two-phase Flow

• Main Authors: Qifang Liu, Yan Han, Zhenyu Liu, Huifang Liu
• Format: Article
• Language: English
• Published: Eastern Macedonia and Thrace Institute of Technology 2015-11-01
• Series: Journal of Engineering Science and Technology Review
• Subjects: : Image reconstruction; FF-H∞ filter; Voidage measurement; ERT sensor
• Online Access: http://www.jestr.org/downloads/Volume8Issue5/fulltext85272015.pdf
• ISSN: 1791-2377; 1791-2377

Image reconstruction technology based on electrical resistance tomography (ERT) is one of the most critical voidage measurement techniques in two-phase flow because of the technology’s merits, such as visualization, non-intrusiveness, and minimal effect on the environment. However, the reconstruction accuracy of ERT usually presents an enormous challenge because of its ill-posed problems in complexity. A new reconstructed algorithm based on forgetting factor-H∞ filter (FF-H∞ filter) for voidage measurement was developed in this study. The H∞ filter was applied to calculate the filter gain and error matrices for state variable formulation. The forgetting factor was then adaptively adjusted by the residual error of two adjacent times to increase the weight of real-time data and update the status variables with the gain matrix. To reduce the noise information and imaging artifacts, the fuzzy threshold de-noising method was implemented in the data processing. Simulated and practical experiments were combined to contribute to the image reconstruction study. The experiments show that compared with the traditional H∞ filter, the FF-H∞ filter can make better use of the three evaluation indexes, improve the reconstructed quality, and significantly reduce boundary artifacts. This method can obtain highly accurate voidage for online measurement because of its strong real-time data availability and antijamming capacity.