naa a22 4500 510823033 CHVBK 20180411083543.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1007/s12541-013-0299-0 doi (NATIONALLICENCE)springer-10.1007/s12541-013-0299-0 Changes observed in Ao mode due to rotational misalignment of air-coupled transducers in isotropic plates [Elektronische Daten] [Ramadas Chennamsetti, Irfan Khan, Avinash Hood, Makarand Joshi] Misalignments are a major concern, when air-coupled ultrasonic probes are deployed for transmission and reception of Lamb waves. Misalignments between the air-coupled probes result in reduction in amplitude and change in arrival time of the Lamb waves. This reduction in amplitude can give a false alarm in Non-destructive Testing (NDT) applications, if amplitude is the criterion for flaw or damage detection. In the present work, one of the probe's (transmitter or receiver) position was kept fixed, and the other probe was rotated to introduce a misalignment termed ‘rotational misalignment'. This rotation had violated the co-planarity condition, resulting in reduction in amplitude of the received fundamental anti-symmetric mode (Ao) in an isotropic material plate. Interestingly, variation in amplitude of the Ao mode with the rotational misalignment angle revealed that, at certain angular locations, there exists a local maximum and local minimum resembling sync function. Subsequently, the angular location of occurrence of these is attributed to dispersion characteristics of the Ao mode. Korean Society for Precision Engineering and Springer-Verlag Berlin Heidelberg, 2013 Air-coupled probe nationallicence Rotational misalignment nationallicence A o mode nationallicence V air : velocity of acoustic wave in air nationallicence V L : phase velocity of Lamb waves nationallicence Chennamsetti Ramadas Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut Khan Irfan Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut Hood Avinash Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut Joshi Makarand Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut International Journal of Precision Engineering and Manufacturing Springer Berlin Heidelberg 14/12(2013-12-01), 2209-2212 2234-7593 14:12<2209 2013 14 12541 https://doi.org/10.1007/s12541-013-0299-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12541-013-0299-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chennamsetti Ramadas Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut NATIONALLICENCE 700 1- Khan Irfan Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut NATIONALLICENCE 700 1- Hood Avinash Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut NATIONALLICENCE 700 1- Joshi Makarand Composites Research Center, R&DE(E), Alandi Road, 411 015, Dighi, Pune, India aut NATIONALLICENCE 773 0- International Journal of Precision Engineering and Manufacturing Springer Berlin Heidelberg 14/12(2013-12-01), 2209-2212 2234-7593 14:12<2209 2013 14 12541 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer