Investigation of liquid∕solid interface waves with laser excitation and photoelastic effect detection

Abstract

Theoretical and experimental investigations on transparent liquid (water)∕solid (aluminum or steel) interface waves generated by laser pulse and detected with photoelastic effect are reported. When the detection beam of a laser interferometer is skimmed over the water∕solid interface and conjoined with the interface wave propagated in water, an extra optical phase shift is produced. The output signal from the interferometer is proportional to the acoustic pressure in water. The characteristic equation of the liquid∕solid interface wave is derived from elastic wave theory, and the transient response of acoustic pressure in water is simulated by means of inverse Laplace and Hankel transforms. The experimental results of acoustic velocity and wave form for all interface waves are in good agreement with theoretical predictions. They show that the optical detecting method based on photoelastic effect is very powerful for the research of liquid∕solid interface waves.

Structural Health Monitoring of Immersed Structures by Means of Guided Ultrasonic Waves

“…Glorieux and his co-authors (1999Glorieux and his co-authors ( , 2001Glorieux and his co-authors ( , 2002Glorieux and his co-authors ( , 2006 studied acoustic waves at the solidliquid and coated solidliquid interfaces, and investigated the non-linear excitation of leaky Rayleigh and Scholte waves. Han et al (2006) investigated the liquid (water)solid (aluminum or steel) interface waves generated by a laser pulse and detected with photoelastic effect. Desmet et al (1996) used laser excitation to create the Scholte wave at the Plexiglasquartz interface exploiting the transparency of the Plexiglas.…”

Planar head wave induced by pulsed laser ablation in liquid

“…[4][5][6] This process, called pulsed laser ablation in liquid (PLAL), excites a wide range of shock and acoustic waves that are of great interest in fundamental research and applications. [7][8][9][10] In this research, a single nanosecond-pulsed laser beam was focused on an epoxy-resin block immersed in different liquids. The dynamics of PLAL were observed using a custom-designed photoelasticity imaging technique.…”

“…The P-wave that propagates along the solid-liquid interface triggers secondary waves propagating into the liquid at the liquid acoustic speed. This wave is known as the head wave (H-wave) 13,14) or lateral wave 7,15) and appears in a 2D image as inclined lines tangent to the reflected wave. The angle θ between the Hwave and solid-liquid interface is defined by: q = v v sin , l s / where v l and v s is the acoustic speed in the liquid and solid, respectively.…”

Multi-component acoustic characterization of porous media

“…Laser ultrasonics can also be applied to assess the acoustic pressure at the fluid/elastic-solid interface by using a Doppler beam skimming over the surface, normal to the direction of propagation of the wave field (Mattei & Adler, 2000;Han et al, 2006). Then, using the photoelastic effect, the recorded signal can be conver-ted into acoustic pressure (Solodov et al, 2009).…”