Location of micro-cracks in plates using time reversed nonlinear Lamb waves  

作　　者：Yaoxin Liu Aijun He Jiehui Liu Yiwei Mao Xiaozhou Liu 刘尧鑫;何爱军;刘杰惠;毛一葳;刘晓宙(Key Laboratory of Modern Acoustics,Institute of Acoustics and School of Physics,Nanjing University,Nanjing 210093,China;Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;School of Electronic Science and Engineering,Nanjing University,Nanjing 210023,China)

机构地区：[1]Key Laboratory of Modern Acoustics,Institute of Acoustics and School of Physics,Nanjing University,Nanjing 210093,China [2]Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China [3]School of Electronic Science and Engineering,Nanjing University,Nanjing 210023,China

出　　处：《Chinese Physics B》2020年第5期311-317,共7页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2016YFF0203000);the State Key Program of the National Natural Science Foundation of China(Grant No.11834008);the National Natural Science Foundation of China(Grant No.11774167);the Fund from the State Key Laboratory of Acoustics,Chinese Academy of Sciences(Grant No.SKLA201809);the Science Fund from the Key Laboratory of Underwater Acoustic Environment,Chinese Academy of Sciences(Grant No.SSHJ-KFKT-1701);the Natural Science Fund for AQSIQ Technology Research and Development Program,China(Grant No.2017QK125).

摘　　要：A promising tool to detect micro-cracks in plate-like structures is used for generating higher harmonic Lamb waves.In this paper,a method combining nonlinear S0 mode Lamb waves with time reversal to locate micro-cracks is presented and verified by numerical simulations.Two different models,the contact acoustic nonlinearity(CAN)model and the Preisach-Mayergoyz(PM)model,are used to simulate a localized damage in a thin plate.Pulse inversion method is employed to extract the second and fourth harmonics from the received signal.Time reversal is performed to compensate the dispersion of S0 mode Lamb waves.Consequently,the higher harmonics generated from the damaged area can be refocused on their source.By investigating the spatial distribution of harmonic wave packets,the location of micro-cracks will be revealed.The numerical simulations indicate that this method gives accurate locations of the damaged area in a plate.Furthermore,the PM model is proved to be a suitable model to simulate the micro-cracks in plates for generation of higher harmonics.

关 键 词：Lamb waves higher harmonics time reversal damage location 

分 类 号：TP274.53[自动化与计算机技术—检测技术与自动化装置]