为了实现工业生产流水线中灌装溶液杂质的在线检测,提高生产检测效率,文中着重研究了基于水听器传感器的在线声波检测技术。通过分析比较在有无固体异物杂质颗粒时灌装容器内的声场频谱分布情况,利用等级相似性系数来定性地判定容器内...为了实现工业生产流水线中灌装溶液杂质的在线检测,提高生产检测效率,文中着重研究了基于水听器传感器的在线声波检测技术。通过分析比较在有无固体异物杂质颗粒时灌装容器内的声场频谱分布情况,利用等级相似性系数来定性地判定容器内溶液的杂质颗粒有无情况。采用水听器作为收集容器内声场数据的传感器,具有体积小、线性工作频率范围宽和无水平指向性等特点。主要步骤有水听器采集声场数据、信号滤波放大、数据采集和FFT数据处理等。通过试验得出结论,容器内的固体异物杂质颗粒在溶液中的声场频谱分布中的特征频段范围是15～26.8 k Hz。展开更多
For solving the difficult problem of leakage detection in city gas pipelines, a method using acoustic technique based on instantaneous energy (IE) distribution and correlation analysis was proposed. Firstly, the basic...For solving the difficult problem of leakage detection in city gas pipelines, a method using acoustic technique based on instantaneous energy (IE) distribution and correlation analysis was proposed. Firstly, the basic theory of leakage detection and location was introduced. Then the physical relationship between instantaneous energy and structural state variation of a system was analyzed theoretically. With HILBERT-HUANG transformation (HHT), the instantaneous energy distribution feature of an unstable acoustic signal was obtained. According to the relative contribution method of the instantaneous energy, the noise in signal was eliminated effectively. Furthermore, in order to judge the leakage, the typical characteristic of the instantaneous energy of signal in the input and output end was discussed using correlative analysis. A number of experiments were carried out to classify the leakage from normal operations, and the results show that the leakages are successfully detected and the average recognition rate reaches 93.3% among three group samples. It is shown that the method using acoustic technique with IED and correlative analysis is effective and it may be referred in other pipelines.展开更多
文摘为了实现工业生产流水线中灌装溶液杂质的在线检测,提高生产检测效率,文中着重研究了基于水听器传感器的在线声波检测技术。通过分析比较在有无固体异物杂质颗粒时灌装容器内的声场频谱分布情况,利用等级相似性系数来定性地判定容器内溶液的杂质颗粒有无情况。采用水听器作为收集容器内声场数据的传感器,具有体积小、线性工作频率范围宽和无水平指向性等特点。主要步骤有水听器采集声场数据、信号滤波放大、数据采集和FFT数据处理等。通过试验得出结论,容器内的固体异物杂质颗粒在溶液中的声场频谱分布中的特征频段范围是15～26.8 k Hz。
基金Project(51004005) supported by the National Natural Science Foundation of ChinaProject supported by Open Research Fund Program of Beijing Engineering Research Center of Monitoring for Construction Safety (Beijing University of Civil Engineering and Architecture), China
文摘For solving the difficult problem of leakage detection in city gas pipelines, a method using acoustic technique based on instantaneous energy (IE) distribution and correlation analysis was proposed. Firstly, the basic theory of leakage detection and location was introduced. Then the physical relationship between instantaneous energy and structural state variation of a system was analyzed theoretically. With HILBERT-HUANG transformation (HHT), the instantaneous energy distribution feature of an unstable acoustic signal was obtained. According to the relative contribution method of the instantaneous energy, the noise in signal was eliminated effectively. Furthermore, in order to judge the leakage, the typical characteristic of the instantaneous energy of signal in the input and output end was discussed using correlative analysis. A number of experiments were carried out to classify the leakage from normal operations, and the results show that the leakages are successfully detected and the average recognition rate reaches 93.3% among three group samples. It is shown that the method using acoustic technique with IED and correlative analysis is effective and it may be referred in other pipelines.
