基于相关运算的声弹性法螺栓预紧力测量  

Bolt preload measurement based on acoustic elasticity method with correlation processing

作　　者：韩玉强 吴付岗[1] 李明海[1] 梅军[1] HAN Yuqiang;WU Fugang;LI Minghai;MEI Jun(Institute of System Engineering,China Academy of Engineering Physics,Mianyang Sichuan 621999,China)

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621999

出　　处：《太赫兹科学与电子信息学报》2022年第8期857-862,共6页Journal of Terahertz Science and Electronic Information Technology

摘　　要：为了在低压激励条件下,利用声弹性准确测量螺栓预紧力,提出采用基于相关运算的信号处理方法。该方法通过比较发射波在接收波中最相似位置获得超声传播时间,从而测量预紧力;相关运算对噪声具有抑制能力,可以实现低信噪比下的传输时间测量,结合内插可提高时间测量分辨力;选择线性调频脉冲作为发射波,开展不同电压激励下的声弹性螺栓预紧力测试。确定了超声传播时间的最大误差不超过±2.9%。测试结果表明:该方法能够实现低压激励条件下超声传播时间的准确测量,结合内插法可以提高时间测量的分辨力。In order to measure the bolt preload with acoustoelasticity accurately under the low voltage excitation,a signal processing method based on correlation operation is utilized to process the echo signal.In this method,the ultrasonic propagation time is obtained by comparing the most similar position of the transmitted wave in the echo,so as to measure the preload.The correlation operation can suppress the noise,which can realize the measurement of transmission time under the condition of low SNR.At the same time,the method combined with interpolation can improve the resolution of time measurement.The Linear Frequency Modulation(LFM)pulse is chosen as the emission wave to test the preload of the bolt using acoustoelasticity under different voltage excitation.The maximum error is below 2.9%.The test results show that the method can realize the accurate measurement of ultrasonic propagation time under the condition of low voltage excitation,and the resolution of time measurement can be improved by combining the interpolation method.

关 键 词：声弹性 传播时间 相关计算 低压激励 

分 类 号：TB553[理学—物理]