摘要
声发射检测方法具有实时动态监测优点,应用越来越广泛,但是对声源的定位始终没有更大的突破。在钢板声发射检测中,提出一种基于时间反转理论的声发射源准确定位的方法。由于声发射检测是一种被动检测技术,结合时间反转聚焦理论,推导出对声源信号实现时间反转聚焦增强处理方法,可增强检测信号中声源幅值,提高信噪比;然后根据声源信号到达时间推算出声源聚焦时刻,利用弹性波传播理论对传感器监测区域重建信号传播波动图,显示出声源位置和区域;最后通过实验测试对该方法进行验证,结果表明该方法能有效提高损伤声源信号的能量,对检测区域的信号重建和定位显示准确地给出损伤声源位置。
Acoustic emission (AE) testing method can realize real-time dynamic monitoring, thus it has been widely applied. However, there is still no breakthrough in the location of AE source. A method based on time reversal theory is proposed to accurately locate the acoustic emission source on the detection of steel plate. Because acoustic emission testing is a passive monitoring method, the processing method of time reversal focusing and enhancing to AE source signal can be achieved according to time reversal theory, by which AE source signal will be amplified and the signal to noise ratio (SNR) will be enhanced. Then the AE source focusing time can be calculated according to the AE source arriving time, and the signal propagation wave image can be reconstructed by taking advantage of the elastic wave propagation theory, and the position of AE source is revealed through the signal focusing. Finally, the method has been verified through experiments, and the results show that the proposed method can effectively improve signal energy of the damage source, and the position of the damage source can be shown accurately through signal reconstruction and location in the detection area.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2016年第8期1792-1799,共8页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(11264032)
江西省自然科学基金(20122BAB201024)
国家质检总局科技计划项目(2013zjjz180)
航空科学基金(2014ZD56007)
上海航天科技创新基金(SAST201364)
江西省教育厅科技项目(GJJ14530)资助
关键词
声发射检测
钢板
时间反转聚焦
信噪比
损伤声源定位
acoustic emission (AE) testing
steel plate
time reversal focusing
singal noise ratio (SNR)
damage source location
作者简介
李昕,2013年于东华理工大学获得学士学位,现为南昌航空大学硕士研究生,主要研究方向为声发射检测技术及检测成像算法等。E-mail:478967251@qq.com罗更生,2006年于南昌航空大学获得硕士学位,现为湖南省特种设备检验检测研究院高工、中南大学在读博士,主要研究方向为压力容器和压力管道声学检测等方面的研究。E-mail:110919954@qq.com李秋锋(通讯作者),2008年于南京航空航天大学获得博士学位,现在为南昌航空大学副教授、硕士生导师,主要研究方向为声学检测及检测信号处理等方面的研究。E-mail:qiufenglee@nuaa.edu.cn