Title :
A study in wedge waves with applications in delay-line
Author :
Po-Hsien Tung ; Che-Hua Yang
Author_Institution :
Inst. of Mech. & Electr. Eng., Nat. Taipei Univ. of Technol., Taipei, Taiwan
Abstract :
Wedge waves are guided acoustic waves propagating along the tip of a wedge. Wedge waves has large motion amplitude and low energy attenuation when tip with small truncation. The difficulty of traditional probe measurement is hard to avoid noise from coupling agent and to raise spatial resolution by contact area. Before using wedge delay line transducer need to know the effect if wedge exist defect in tip. This study using laser ultrasound technique (LUT) and finite element method (FEM) is used to characterize the ASF modes propagation along wedge tips with defects. Defect parameter of depth are discussed regarding to their influences on the reflection coefficient (RC) and transmission coefficient (TC). Also this study discover wedge wave has mode conversion (MC) at tip with defect.
Keywords :
finite element analysis; shapes (structures); structural acoustics; ultrasonic propagation; ultrasonic reflection; ultrasonic transmission; ASF mode propagation; FEM; LUT; Wedge waves; contact area; coupling agent; defect parameter; finite element method; guided acoustic wave propagation; laser ultrasound technique; low energy attenuation; raise spatial resolution; reflection coefficient; traditional probe measurement; transmission coefficient; wave motion amplitude; wedge delay line transducer; wedge wave tip; Acoustics; Dispersion; Finite element analysis; Laser modes; Measurement by laser beam; Ultrasonic imaging; Ultrasonic variables measurement; defect; mode conversion; reflected coefficient; transmitted coefficient; wedge delay-line;
Conference_Titel :
Ultrasonics Symposium (IUS), 2013 IEEE International
Conference_Location :
Prague
Print_ISBN :
978-1-4673-5684-8
DOI :
10.1109/ULTSYM.2013.0418
