Benmeddour Farouk, Grondel Sébastien, Assaad Jamal, Moulin Emmanuel
IEMN, UMR/CNRS 8520, OAE Department, Université de Valenciennes et du Hainaut Cambrésis, Valenciennes Cedex 9, France.
Ultrasonics. 2009 Feb;49(2):202-5. doi: 10.1016/j.ultras.2008.08.002. Epub 2008 Aug 15.
The aim of this work is to study the fundamental Lamb modes interaction with defects in isotropic plates. For these experimental investigations, symmetrical notches with various depths milled in aluminum plates are considered. Moreover, the incident Lamb wave of a specific mode is generated by means of two identical thin piezoceramic transducers placed at the opposite sides of the plate. The waves scattered by the notch are recorded with conventional transducers located on the plate surface in front and behind the defect. The selection of the A(0) or the S(0) modes is obtained by exciting the transducers with anti-phased or in-phased signals, respectively. Furthermore, a calibration process is investigated to correct errors caused by the presence of the receiver between the emitters and the defects. The power reflection and transmission coefficients are then obtained and the power balance is verified. Finally, these measurements are compared successfully with those obtained by a numerical method using the finite-element modeling described in a previous work.
这项工作的目的是研究各向同性板中基本兰姆波与缺陷的相互作用。对于这些实验研究，考虑在铝板上铣削出不同深度的对称切口。此外，通过放置在板相对两侧的两个相同的薄压电陶瓷换能器产生特定模式的入射兰姆波。由切口散射的波用位于缺陷前方和后方板表面上的传统换能器进行记录。分别通过用反相或同相信号激励换能器来选择A(0)或S(0)模式。此外，研究了一种校准过程，以校正由于发射器和缺陷之间存在接收器而引起的误差。然后获得功率反射和传输系数，并验证功率平衡。最后，将这些测量结果与使用先前工作中描述的有限元建模的数值方法获得的测量结果成功进行了比较。
