B. Zhang et Re. Imhof, Thermally coupled interfacial acoustic waves observed in transient surface-grating measurements, P ROY SOC A, 456(2003), 2000, pp. 2781-2798
Citations number
8
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary
Journal title
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
We report the observation of interfacial acoustic waves in the gas above op
aque condensed media excited by pulsed laser radiation in transient surface
-grating experiments. They differ from previously described interfacial wav
es in the coupling between the media: Stoneley, Scholte and others describe
d elastically coupled interfacial waves, whereas our analysis, based on app
roximate solutions of the Navier-Stokes equations, shows that thermal coupl
ing is dominant in this case. Our model relates the amplitude and phase vel
ocity of these interfacial waves to the thermal, elastic and optical proper
ties of the adjoining media. The new thermo-acoustic effect may be of use i
n the study of thermal and elastic properties of gases at frequencies above
1 MHz, where conventional ultrasonic techniques fail.