On the Propagation of Sound Waves in Two-Phase Fluids

Abstract

The governing equations for the propagation of sound waves through a dispersed two-phase fluid are derived. The fluid considered is composed of two phases of a fluid in a state of thermodynamic nonequilibrium such as evaporating or condensing droplets entrained in the vapor phase, which is slightly superheated or at the saturation state. The field equations show that the propagation of the waves can depend on a change-of-phase function, which when put equal to zero reduces the equations to the standard ones. It is shown that the change-of-phase function depends on the pressure, and it becomes oscillatory with respect to time with the passage of sound waves. The influence of the change-of-phase function on sound propagation, attenuation, and intensity are found to be significant when the function's value is not small.