Acoustics of a bubbly fluid at large bubble concentration

Claude Boutin (1) , Jean-Louis Auriault (2, 3)

1 DGCB-LGM - Laboratoire Géomatériaux
2 IMG - Institut de Mécanique de Grenoble (IMG)
3 INPG - Institut National Polytechnique de Grenoble

The homogenization process is used to investigate how acoustic waves propagate in a bubbly fluid at finite concentration. This method involves the consideration of waves whose lengths are large compared with the bubble size. We focus on the linear domain, with viscous, thermal and capillary effects. It is shown that this medium displays three different macroscopic descriptions according to bubble diameter and wave frequency. For bubbles of small size, the capillary effect leads to a model where in acoustic waves are either propagative with low celerity or diffusive. On increasing the bubble diameter we obtain waves which are damped and dispersed by both viscous and thermal effects. Finally for large bubbles, we get biphasic undamped and dispersed waves. Moreover, the homogenization method allows us to predict the kind of behaviour and the accuracy of the model from a knowledge of the physical characteristics of the mixture. Applications of these results are presented in the case of water containing air bubbles in equal proportion.

Domaines: Mécanique [physics.med-ph]

Claude Boutin, Jean-Louis Auriault. Acoustics of a bubbly fluid at large bubble concentration. European Journal of Mechanics - B/Fluids, 1993, 12 (3), pp.367-399. ⟨hal-00940459⟩