J042012 Resonant phenomena of the circumferential Lamb waves generated and detected by eight transducer-elements located evenly on circumference and their application to wall thickness measurements.

Abstract

Resonant phenomena of the circumferential Lamb waves generated and detected by eight transducer − elements located even 且 y on circumference and their apPlication to wall thickness measurements ． Keiichi MORI 工A ＊ 1 ，Kohei TAKEHARA ， and Hideo NISHINO ' 1The University ofTokushima Minami 一 亅 yosanjima2 − 1， Tokushima 770 − 8506， Japan Aresonant phenomenon of the circumferential ( C − ) Lamb wave generated by eight transducer elements located evenly on the circumference was shown ， The eight transducer elemcnts on a pipe surface are none other than 吐 he sensor system for transduction ofaxial guided waves ， Because the resonant condition of the phenomenon depends on the wall thickness ， we proposed a novel method for estimating the wall thickness ． In this paper， thc principle ， theoretical