Finite difference time domain simulation of the time-of-flight diffraction technique for imaging and sizing cracks
Authors: Satyanarayan, L; Krishnamurthy, C V; Balasubramaniam, K
Source: Insight - Non-Destructive Testing and Condition Monitoring, Volume 49, Number 12, December 2007 , pp. 708-714(7)
Abstract:This paper reports on the numerical simulations of the Time-of-Flight Diffraction (TOFD) technique to image and size cracks in plate specimens, using the Finite Difference Time Domain (FDTD) method for modelling the ultrasonic wave propagation. Experiments were conducted to validate modelling results for pitch-catch simulations of transducers on samples with calibrated defects of different configurations and sizes in aluminium plate sections. Defects were imaged and sized taking into consideration the velocity of the wave and the times of arrival of the diffracted echoes. Experiments were carried out using a 5 MHz transmitter-receiver transducer pair mounted on suitable wedges to generate a beam of 50 refracted angle within the specimen to image and size cracks and hence validate the simulations. A front/back-wall correction algorithm coupled with a synthetic aperture focusing of the TOFD signals was also demonstrated for improved sizing of defects.
Document Type: Research article
Affiliations: 1: 1 Project Officer in the Center for Non-Destructive Evaluation in the Department of Mechanical Engineering, IIT Madras. His research interests are non-destructive evaluation, acoustics, signal processing and finite element analysis.
Publication date: 2007-12-01
- Official Journal of The British Institute of Non-Destructive Testing - includes original research and devlopment papers, technical and scientific reviews and case studies in the fields of NDT and CM.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Information for Advertisers
- Terms & Conditions
- ingentaconnect is not responsible for the content or availability of external websites