Study of two-phase bubbly flow dynamics in binary mixtures

The results of an investigation of the bubble dynamics and wave phenomena in two-component vapor-liquid mixtures are presented. These mixtures are widely used in industrial systems as heat transfer media. The effects of various additives on the wave dynamics of vapor-liquid mixtures are of particular interest. A single-velocity two-pressure model was used which takes into account both the liquid radial inertia due to medium volume changes, and the temperature distribution around the bubbles. The claim that mixture composition may have a peculiar effect on the bubble dynamics of a boiling non-ideal solution is substantiated. It is noted that the small free radial oscillation damping ratio for some binary systems lies outside the domain defined by the damping ratio of the constituents as a result of phase change diffusion effects. A criterion is proposed to identify cases of diffusion resistance responsible for the anomalous effect of component concentration on bubble behavior. The phase change delay due to diffusion results in observably higher mixture wave velocities and a smaller damping ratio than for respective single-component systems.