title: Localization of CO₂ Leakage from a Circular Hole on a Flat-Surface Structure Using a Circular Acoustic Emission Sensor Array.
abstract: Leak localization is essential for the safety and maintenance of storage vessels. This study proposes a novel circular acoustic emission sensor array to realize the continuous CO₂ leak localization from a circular hole on the surface of a large storage vessel in a carbon capture and storage system. Advantages of the proposed array are analyzed and compared with the common sparse arrays. Experiments were carried out on a laboratory-scale stainless steel plate and leak signals were obtained from a circular hole in the center of this flat-surface structure. In order to reduce the influence of the ambient noise and dispersion of the acoustic wave on the localization accuracy, ensemble empirical mode decomposition is deployed to extract the useful leak signal. The time differences between the signals from the adjacent sensors in the array are calculated through correlation signal processing before estimating the corresponding distance differences between the sensors. A hyperbolic positioning algorithm is used to identify the location of the circular leak hole. Results show that the circular sensor array has very good directivity toward the circular leak hole. Furthermore, an optimized method is proposed by changing the position of the circular sensor array on the flat-surface structure or adding another circular sensor array to identify the direction of the circular leak hole. Experiential results obtained on a 100 cm × 100 cm stainless steel plate demonstrate that the full-scale error in the leak localization is within 0.6%.
authors.affiliation: School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China. cuixiwang@ncepu.edu.cn.
authors.forename: Xiwang
authors.initials: X
authors.lastname: Cui
authors.affiliation: School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China. y.yan@kent.ac.uk.|School of Engineering and Digital Arts, University of Kent, Canterbury, Kent CT2 7NT, UK. y.yan@kent.ac.uk.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yan
authors.affiliation: School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China. guomiao@ncepu.edu.cn.
authors.forename: Miao
authors.initials: M
authors.lastname: Guo
authors.affiliation: School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China. hxj@ncepu.edu.cn.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Han
authors.affiliation: School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China. yhhu@ncepu.edu.cn.
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Hu
keywords: CO2 leakage; acoustic emission; circular sensor array; leak localization