Cui Xiwang, Yan Yong, Guo Miao, Han Xiaojuan, Hu Yonghui
School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China.
School of Engineering and Digital Arts, University of Kent, Canterbury, Kent CT2 7NT, UK.
Sensors (Basel). 2016 Nov 19;16(11):1951. doi: 10.3390/s16111951.
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%.
泄漏定位对于储存容器的安全和维护至关重要。本研究提出了一种新型圆形声发射传感器阵列，以实现碳捕获与储存系统中大型储存容器表面圆形孔洞的连续二氧化碳泄漏定位。分析了所提阵列的优点，并与常见的稀疏阵列进行了比较。在实验室规模的不锈钢板上进行了实验，从该平面结构中心的圆形孔洞获取了泄漏信号。为了降低环境噪声和声波色散对定位精度的影响，采用总体经验模态分解来提取有用的泄漏信号。在估计传感器之间相应的距离差之前，通过相关信号处理计算阵列中相邻传感器信号之间的时间差。采用双曲线定位算法来确定圆形泄漏孔的位置。结果表明，圆形传感器阵列对圆形泄漏孔具有很好的指向性。此外，还提出了一种优化方法，通过改变圆形传感器阵列在平面结构上的位置或增加另一个圆形传感器阵列来确定圆形泄漏孔的方向。在100 cm×100 cm不锈钢板上获得的实验结果表明，泄漏定位的满量程误差在0.6%以内。
