EFFECTIVE-MEDIUM MODEL FOR ULTRASONIC-ATTENUATION DUE TO THE THERMOELASTIC EFFECT IN CONCENTRATED EMULSIONS

In this article, are deal with the propagation of ultrasonic waves in monodisperse concentrated oil-in-water emulsions. Using the approximat ion of Isakovich, we propose two different models, a mirror model and a core-shell model, aiming to describe the temperature field in the de nse medium and to supply a correct expression of the ultrasonic wave v ector. The comparison between experimental data and theoretical models shows that the core-shell model leads to a very accurate description of the ultrasonic attenuation, in a wide range of frequencies and conc entrations, in the case where the thermo-elastic effect, due to the sc attering of thermal waves by the particles, is the dominant loss mecha nism.