Low attenuation frequency bands for Lamb waves immersed in viscous fluids: theoretical analysis and experimental validation.

Abstract

The application of Lamb waves is a promising technique i n ultrasonic NDE techniques for inspection and fluid characterization due to multi modal and dispersive characteristics. When a plate is in contact with a viscous fluid these waves are strongly attenuated. However, for most of the Lamb wave modes there is a low at tenuation frequency band that could be used for non-destructive testing or fluid characteriz ation. In order to explore this feature the phase velocity and attenuation curves of Lamb modes are expe rimentally measured in these low attenuation frequency bands, showing good agreement with theory .