Effect of viscosity on propagation properties of acoustic waves in liquids with bubbles

Abstract

In this paper, propagation properties of linear acoustic waves in viscous liquids with bubbles are studied by using the effective medium theory. The attenuation coefficient and the phase velocity of waves are investigated. The influence of the viscosity on the wave equation and the vibration equation of bubble is considered. Research results show the resonance absorption of acoustic waves is caused by the resonance of bubble and influenced by the interaction of bubbles. The interaction results in the difference between the resonance absorption frequency of waves and the resonance frequency of bubble, and makes the frequency width of resonance absorption regions of waves become large. In non-resonance regions, the influence of the viscosity and the volume fraction of gas on low-frequency acoustic waves is investigated. The viscosity can influence acoustic waves through the wave equation and the vibration equation of bubble. We analyze the effect of the two ways, and give conditions for some approximation theories.