Lamb wave localization and imaging of crack originating from a through-hole by fusing Radon transform
Based on the basic principle of the interaction between Lamb waves of different modes and cracks originating from a through-hole,the current work focused on the precise detection of time-of-flight(ToF)for Lamb wave packets of different modes,and implements the Lamb wave localization and imaging of cracks originating from a through-hole by fusing Radon transform with taking the crack originating from the hole in an isotropic plate as the research object.Firstly,a broadband chirp signal was used to excite the sparse sensor array for the generation of Lamb waves,and the scattering signals of through-hole were obtained as the baseline signals,where the scattering ones of the crack originating from the hole were collected as monitoring signals.Secondly,the chirp response signals were filtered and the center frequency and modulation cycle number of the corresponding narrowband responses of tone burst were optimized.Then,the Radon transform was performed on the baseline singles of tone burst response to obtain the optimized group velocity and offset time,and the ToF of Lamb wave packet was calculated.Finally,the elliptical imaging algorithm was used to locate and image the crack originating from the hole,and the imaging results were compared with those by the nominal group velocity method.The results showed that the ToF of Lamb wave packet can be accurately calculated with the fusion of Radon transform,which improved the detection capability of different modal Lamb waves for the defects of crack originating from the hole.
Radon transformcracksLamb wavelocalization and imaging algorithmtime-of-flight
NETL
NSTL
万方数据
维普
