基于Lorenz系统Lyapunov指数的管道超声导波检测

Abstract: In order to improve detection precision of ultrasonic guided wave in a long-distance pipeline, a pipeline ultrasonic guided wave detection method based on Lyapunov exponent of Lorenz system was proposed. Lorenz system * s chaos control was realized based on parametric excitation of non-resonant periodic signals. Guided wave signals to be detected, as the disturbance term of parametric excitation, were inputted into Lorenz detection system. The response of Lorenz system' s maximum Lyapunov exponent after inputting guided wave signals was compared to that without inputting guided wave ones to determine parametric excitation amplitude suitable for guided wave signal detection. The software ANSYS and a test platform for ultrasonic guided wave were used to do numerical simulation and tests, respectively to acquire ultrasonic guided wave * s simulated signals and test ones propagating in a 6-meter long steel pipe with different sizes and numbers of damage. Then Lorenz system was used to detect these simulated signals and test ones. The guided wave signals were recognized in segments based on the dichotomy. The damages were positioned through locating the time period of echo signals. The detection results showed that Lorenz system is immune to noise, it can effectively recognize damages or defects in a pipeline, and improve the sensitivity of pipeline ultrasonic guided wave detection.
第38卷第11期
振动与冲击 JOURNAL OF VIBRATION AND SHOCK
Vol. 38 No. 11 2019
基于Lorenz系统Lyapunov指数的管道超声导波检测
温宇立巴武静S林荣2,马宏伟邛
(1.广东海洋大学机械与动力工程学院，广东湛江524088 ；2,东莞理工学院建筑工程系，广东东莞523808； 3.暨南大学力学与建筑工程学院，广州510632)
(1. School of Mechanical and Power Engineering, Guangdong Ocean University, Zhanjiang 524088 , China ； 2. Department of Civil Engineering, Dongguan University of Technology, Dongguan 523808 , China ； 3. School of Mechanics and Construction Engineering, Jinan University, Guangzhou 510632, China)
摘 要:为了提高长距离管道超声导波检测中弱导波信号的识别精度，提出了基于Lorenz系统Lyapunov指数的
管道超声导波检测方法。基于非共振周期信号的参数激励实现Lorenz系统的混沌控制，将待测的导波信号作为参数激 励的扰动项输入Lorenz检测系统中，通过对比有无导波信号输入后Lorenz系统最大Lyapunov指数的不同响应，确定适合 导波信号检测的参数激励幅值;然后利用ANSYS软件和搭建的超声导波试验平台分别进行数值模拟和实验，获得超声导 波在含有不同损伤个数、大小的6 m长管道中传播的数值模拟信号和试验信号，利用Lorenz检测系统识别数值模拟与实 验信号;基于二分法对导波信号进行分段识别，通过定位出回波信号的时间段实现损伤定位。检测结果表明.Lorenz系统 能够有效地免疫噪声并识别管道的缺陷,并且提高了管道超声导波检测的灵敏度。
关键词：超声导波;Lorenz系统;混沌;Lyapunov指数
中图分类号：TH2Байду номын сангаас2;TH213.3
文献标志码：A
DOI： 10.13465/j. cnki. jvs.2019.11.038
Ultrasonic guided wave detection in a pipeline based on Lyapunov exponent of Lorenz system WEN Yuli1'3, WU Jing , UN Rong , MA Hongwe^3