Are bubbly flows more stable than we thought? This paper explores the effects of bubble dynamics on the stability of two-dimensional parallel bubbly flows, considering arbitrary vapor-gas contents and low void fractions. Linear perturbation equations are derived for stability analysis, incorporating bubble compressibility, inertia, and energy dissipation, providing insights for controlling cavitation in fluid systems. The analysis includes the viscosity of the liquid and the transfer of heat and mass due to compression/expansion of noncondensable gas and evaporation/condensation of vapor within the bubbles. Numerical solutions of the spatial stability problem are presented for inviscid shear layers and Blasius boundary layers. The results indicate that dispersed phases generally favor stability, showing deviations from classical results for single-phase fluids. The analysis highlights significant differences in stability between flows with noncondensable gas bubbles and cavitating flows with vapor-dominant bubbles, providing valuable insights for designing stable fluid systems.
Appearing in the Journal of Fluids Engineering, this paper aligns with the journal's focus on fluid mechanics and its applications. The study of stability in bubbly cavitating flows is a relevant topic for the journal's readership, contributing to the understanding of complex fluid phenomena.